Browser controls in viz 4: OffsetTag plumbing to renderer

https://chromium-review.googlesource.com/c/chromium/src/+/5535310
plumbed to browser side objects, this cl plumbs to the renderer.

Bug: 325471990, 345261548
Change-Id: I334c13ccdf54978694c8a286f46f06e6096d6d9e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5605504
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Commit-Queue: Peilin Wang <peilinwang@google.com>
Reviewed-by: Rakina Zata Amni <rakina@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Reviewed-by: Kyle Charbonneau <kylechar@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1313038}

cc/input/browser_controls_offset_manager.cc

@@ -11,9 +11,12 @@
 
 #include "base/check_op.h"
 #include "base/memory/ptr_util.h"
+#include "base/types/optional_ref.h"
 #include "cc/input/browser_controls_offset_manager_client.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/trees/layer_tree_impl.h"
 #include "components/viz/common/frame_sinks/begin_frame_args.h"
+#include "components/viz/common/quads/offset_tag.h"
 #include "ui/gfx/animation/tween.h"
 #include "ui/gfx/geometry/transform.h"
 #include "ui/gfx/geometry/vector2d_f.h"
@@ -80,6 +83,10 @@ float BrowserControlsOffsetManager::TopControlsMinHeight() const {
   return client_->TopControlsMinHeight();
 }
 
+viz::OffsetTag BrowserControlsOffsetManager::TopControlsOffsetTag() const {
+  return top_controls_offset_tag_;
+}
+
 float BrowserControlsOffsetManager::TopControlsMinShownRatio() const {
   return TopControlsHeight() ? TopControlsMinHeight() / TopControlsHeight()
                              : 0.f;
@@ -137,7 +144,8 @@ BrowserControlsOffsetManager::BottomControlsShownRatioRange() {
 void BrowserControlsOffsetManager::UpdateBrowserControlsState(
     BrowserControlsState constraints,
     BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info) {
   DCHECK(!(constraints == BrowserControlsState::kShown &&
            current == BrowserControlsState::kHidden));
   DCHECK(!(constraints == BrowserControlsState::kHidden &&
@@ -156,6 +164,10 @@ void BrowserControlsOffsetManager::UpdateBrowserControlsState(
 
   permitted_state_ = constraints;
 
+  if (offset_tags_info.has_value()) {
+    top_controls_offset_tag_ = offset_tags_info.value().top_controls_offset_tag;
+  }
+
   // Don't do anything if it doesn't matter which state the controls are in.
   if (constraints == BrowserControlsState::kBoth &&
       current == BrowserControlsState::kBoth)

cc/input/browser_controls_offset_manager.h

@@ -11,9 +11,12 @@
 
 #include "base/memory/raw_ptr.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "cc/layers/layer_impl.h"
 #include "cc/trees/browser_controls_params.h"
+#include "components/viz/common/quads/offset_tag.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/geometry/vector2d_f.h"
 
@@ -56,6 +59,7 @@ class CC_EXPORT BrowserControlsOffsetManager {
   // min-height, which is equal to the current visible min-height. Otherwise,
   // this will return the same value as |TopControlsMinHeight()|.
   float TopControlsMinHeightOffset() const;
+  viz::OffsetTag TopControlsOffsetTag() const;
 
   // The amount of offset of the web content area, calculating from the bottom.
   // Same as the current shown height of the bottom controls.
@@ -87,9 +91,13 @@ class CC_EXPORT BrowserControlsOffsetManager {
                AnimationDirection::kShowingControls;
   }
 
-  void UpdateBrowserControlsState(BrowserControlsState constraints,
-                                  BrowserControlsState current,
-                                  bool animate);
+  // See UpdateBrowserControlsState in
+  // third_party/blink/public/mojom/frame/frame.mojom
+  void UpdateBrowserControlsState(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info);
 
   // Return the browser control constraint that must be synced to the
   // main renderer thread (to trigger viewport and related changes).
@@ -197,6 +205,11 @@ class CC_EXPORT BrowserControlsOffsetManager {
   // gesture, then we reorder the animation until after the scroll.
   bool show_controls_when_scroll_completes_ = false;
 
+  // The tag used to accompany scroll offsets in the render frame's metadata.
+  // During surface aggregation, the layers with the same token will have the
+  // corresponding offsets applied.
+  viz::OffsetTag top_controls_offset_tag_;
+
   // Class that holds and manages the state of the controls animations.
   class Animation {
    public:

cc/input/browser_controls_offset_manager_unittest.cc

@@ -982,7 +982,8 @@ TEST(BrowserControlsOffsetManagerTest, ScrollByWithZeroHeightControlsIsNoop) {
   MockBrowserControlsOffsetManagerClient client(0.f, 0.5f, 0.5f);
   BrowserControlsOffsetManager* manager = client.manager();
   manager->UpdateBrowserControlsState(BrowserControlsState::kBoth,
-                                      BrowserControlsState::kBoth, false);
+                                      BrowserControlsState::kBoth, false,
+                                      std::nullopt);
 
   manager->ScrollBegin();
   gfx::Vector2dF pending = manager->ScrollBy(gfx::Vector2dF(0.f, 20.f));
@@ -1053,12 +1054,14 @@ TEST(BrowserControlsOffsetManagerTest,
   EXPECT_FLOAT_EQ(1.f, client.CurrentBottomControlsShownRatio());
 
   manager->UpdateBrowserControlsState(BrowserControlsState::kBoth,
-                                      BrowserControlsState::kHidden, true);
+                                      BrowserControlsState::kHidden, true,
+                                      std::nullopt);
   EXPECT_TRUE(manager->HasAnimation());
   EXPECT_FLOAT_EQ(1.f, client.CurrentBottomControlsShownRatio());
 
   manager->UpdateBrowserControlsState(BrowserControlsState::kBoth,
-                                      BrowserControlsState::kShown, true);
+                                      BrowserControlsState::kShown, true,
+                                      std::nullopt);
   EXPECT_FALSE(manager->HasAnimation());
   EXPECT_FLOAT_EQ(1.f, client.CurrentBottomControlsShownRatio());
 }
@@ -1214,7 +1217,8 @@ TEST(BrowserControlsOffsetManagerTest, MinHeightChangeUpdatesAnimation) {
   // Hide the controls to start an animation to min-height.
   EXPECT_FLOAT_EQ(1.f, manager->TopControlsShownRatio());
   manager->UpdateBrowserControlsState(BrowserControlsState::kHidden,
-                                      BrowserControlsState::kBoth, true);
+                                      BrowserControlsState::kBoth, true,
+                                      std::nullopt);
   base::TimeTicks time = base::TimeTicks::Now();
   manager->Animate(time);
   EXPECT_TRUE(manager->HasAnimation());
@@ -1314,7 +1318,8 @@ TEST(BrowserControlsOffsetManagerTest,
 
   // Start an animation to show the controls
   manager->UpdateBrowserControlsState(BrowserControlsState::kBoth,
-                                      BrowserControlsState::kShown, true);
+                                      BrowserControlsState::kShown, true,
+                                      std::nullopt);
   EXPECT_TRUE(manager->IsAnimatingToShowControls());
 
   // Start a scroll, which should cancel the animation.
@@ -1349,7 +1354,8 @@ TEST(BrowserControlsOffsetManagerTest,
 
   // Start an animation to show the controls.
   manager->UpdateBrowserControlsState(BrowserControlsState::kBoth,
-                                      BrowserControlsState::kShown, true);
+                                      BrowserControlsState::kShown, true,
+                                      std::nullopt);
   EXPECT_TRUE(manager->IsAnimatingToShowControls());
 
   // Finish the scroll, and the animation should still be in progress and/or

cc/input/compositor_input_interfaces.h

@@ -8,7 +8,9 @@
 #include <memory>
 
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
 #include "cc/input/actively_scrolling_type.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "cc/paint/element_id.h"
 #include "ui/gfx/geometry/size.h"
@@ -136,9 +138,12 @@ class CompositorDelegateForInput {
   virtual float PageScaleFactor() const = 0;
   virtual gfx::Size VisualDeviceViewportSize() const = 0;
   virtual const LayerTreeSettings& GetSettings() const = 0;
-  virtual void UpdateBrowserControlsState(BrowserControlsState constraints,
-                                          BrowserControlsState current,
-                                          bool animate) = 0;
+  virtual void UpdateBrowserControlsState(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo>
+          offset_tags_info) = 0;
   virtual bool HasScrollLinkedAnimation(ElementId for_scroller) const = 0;
 
   // TODO(bokan): Temporary escape hatch for code that hasn't yet been

cc/input/input_handler.cc

@@ -10,9 +10,11 @@
 
 #include "base/feature_list.h"
 #include "base/notreached.h"
+#include "base/types/optional_ref.h"
 #include "build/build_config.h"
 #include "cc/base/features.h"
 #include "cc/input/browser_controls_offset_manager.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/scroll_elasticity_helper.h"
 #include "cc/input/scroll_utils.h"
 #include "cc/input/scrollbar_controller.h"
@@ -2115,11 +2117,13 @@ void InputHandler::SetDeferBeginMainFrame(bool defer_begin_main_frame) const {
   compositor_delegate_->SetDeferBeginMainFrame(defer_begin_main_frame);
 }
 
-void InputHandler::UpdateBrowserControlsState(BrowserControlsState constraints,
-                                              BrowserControlsState current,
-                                              bool animate) {
+void InputHandler::UpdateBrowserControlsState(
+    BrowserControlsState constraints,
+    BrowserControlsState current,
+    bool animate,
+    base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info) {
   compositor_delegate_->UpdateBrowserControlsState(constraints, current,
-                                                   animate);
+                                                   animate, offset_tags_info);
 }
 
 void InputHandler::SetIsHandlingTouchSequence(bool is_handling_touch_sequence) {

cc/input/input_handler.h

@@ -11,7 +11,9 @@
 #include "base/memory/raw_ptr.h"
 #include "base/memory/raw_ref.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
 #include "cc/cc_export.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "cc/input/compositor_input_interfaces.h"
 #include "cc/input/event_listener_properties.h"
@@ -438,9 +440,11 @@ class CC_EXPORT InputHandler : public InputDelegateForCompositor {
   // compositor thread has had a chance to update the scroll offset.
   virtual void SetDeferBeginMainFrame(bool defer_begin_main_frame) const;
 
-  virtual void UpdateBrowserControlsState(BrowserControlsState constraints,
-                                          BrowserControlsState current,
-                                          bool animate);
+  virtual void UpdateBrowserControlsState(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info);
 
   virtual void SetIsHandlingTouchSequence(bool is_handling_touch_sequence);
 

cc/mojom/BUILD.gn

@@ -22,6 +22,7 @@ component("shared_mojom_traits") {
 mojom("mojom") {
   generate_java = true
   sources = [
+    "browser_controls_offset_tags_info.mojom",
     "browser_controls_params.mojom",
     "browser_controls_state.mojom",
     "overscroll_behavior.mojom",
@@ -86,6 +87,17 @@ mojom("mojom") {
       traits_headers = [ "//cc/ipc/cc_param_traits_macros.h" ]
       traits_public_deps = [ "//cc/ipc" ]
     },
+    {
+      types = [
+        {
+          mojom = "cc.mojom.BrowserControlsOffsetTagsInfo"
+          cpp = "::cc::BrowserControlsOffsetTagsInfo"
+        },
+      ]
+      traits_headers =
+          [ "//cc/mojom/browser_controls_offset_tags_info_mojom_traits.h" ]
+      traits_public_deps = [ "//components/viz/common" ]
+    },
     {
       types = [
         {

cc/mojom/DEPS

@@ -1,5 +1,6 @@
 include_rules = [
   "+mojo/public",
   "+services/viz/public/cpp/compositing",
+  "+services/viz/public/mojom/compositing",
   "+skia/public/mojom",
 ]

cc/mojom/browser_controls_offset_tags_info.mojom

@@ -0,0 +1,15 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+module cc.mojom;
+
+import "services/viz/public/mojom/compositing/offset_tag.mojom";
+
+// Only sent from browser to renderer. See
+// cc/input/browser_controls_offset_tags_info.h for more details.
+struct BrowserControlsOffsetTagsInfo {
+  viz.mojom.OffsetTag top_controls_offset_tag;
+  int32 top_controls_height;
+  int32 top_controls_width;
+};

cc/mojom/browser_controls_offset_tags_info_mojom_traits.h

@@ -0,0 +1,41 @@
+// Copyright 2024 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CC_MOJOM_BROWSER_CONTROLS_OFFSET_TAGS_INFO_MOJOM_TRAITS_H_
+#define CC_MOJOM_BROWSER_CONTROLS_OFFSET_TAGS_INFO_MOJOM_TRAITS_H_
+
+#include "cc/input/browser_controls_offset_tags_info.h"
+#include "cc/mojom/browser_controls_offset_tags_info.mojom-shared.h"
+#include "components/viz/common/quads/offset_tag.h"
+#include "services/viz/public/cpp/compositing/offset_tag_mojom_traits.h"
+
+namespace mojo {
+
+template <>
+struct StructTraits<cc::mojom::BrowserControlsOffsetTagsInfoDataView,
+                    cc::BrowserControlsOffsetTagsInfo> {
+  static const viz::OffsetTag& top_controls_offset_tag(
+      const cc::BrowserControlsOffsetTagsInfo& input) {
+    return input.top_controls_offset_tag;
+  }
+
+  static int top_controls_height(
+      const cc::BrowserControlsOffsetTagsInfo& input) {
+    return input.top_controls_height;
+  }
+
+  static int top_controls_width(
+      const cc::BrowserControlsOffsetTagsInfo& input) {
+    return input.top_controls_width;
+  }
+
+  static bool Read(cc::mojom::BrowserControlsOffsetTagsInfoDataView data,
+                   cc::BrowserControlsOffsetTagsInfo* out) {
+    return data.ReadTopControlsOffsetTag(&out->top_controls_offset_tag);
+  }
+};
+
+}  // namespace mojo
+
+#endif  // CC_MOJOM_BROWSER_CONTROLS_OFFSET_TAGS_INFO_MOJOM_TRAITS_H_

cc/test/fake_proxy.h

@@ -9,6 +9,8 @@
 
 #include "base/memory/raw_ptr.h"
 #include "base/task/single_thread_task_runner.h"
+#include "base/types/optional_ref.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/paint_holding_reason.h"
 #include "cc/trees/proxy.h"
@@ -50,9 +52,12 @@ class FakeProxy : public Proxy {
   void SetPaintWorkletLayerPainter(
       std::unique_ptr<PaintWorkletLayerPainter> painter) override;
   bool MainFrameWillHappenForTesting() override;
-  void UpdateBrowserControlsState(BrowserControlsState constraints,
-                                  BrowserControlsState current,
-                                  bool animate) override {}
+  void UpdateBrowserControlsState(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info)
+      override {}
   void RequestBeginMainFrameNotExpected(bool new_state) override {}
   void SetSourceURL(ukm::SourceId source_id, const GURL& url) override {}
   void SetUkmSmoothnessDestination(

cc/trees/layer_tree_host.cc

@@ -30,12 +30,14 @@
 #include "base/timer/elapsed_timer.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/traced_value.h"
+#include "base/types/optional_ref.h"
 #include "build/build_config.h"
 #include "cc/base/devtools_instrumentation.h"
 #include "cc/base/features.h"
 #include "cc/base/histograms.h"
 #include "cc/base/math_util.h"
 #include "cc/debug/rendering_stats_instrumentation.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/layer_selection_bound.h"
 #include "cc/input/overscroll_behavior.h"
 #include "cc/input/page_scale_animation.h"
@@ -1200,13 +1202,16 @@ void LayerTreeHost::DetachInputDelegateAndRenderFrameObserver() {
   proxy_->DetachInputDelegateAndRenderFrameObserver();
 }
 
-void LayerTreeHost::UpdateBrowserControlsState(BrowserControlsState constraints,
-                                               BrowserControlsState current,
-                                               bool animate) {
+void LayerTreeHost::UpdateBrowserControlsState(
+    BrowserControlsState constraints,
+    BrowserControlsState current,
+    bool animate,
+    base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info) {
   DCHECK(IsMainThread());
   // Browser controls are only used in threaded mode but Blink layout tests may
   // call into this. The single threaded version is a no-op.
-  proxy_->UpdateBrowserControlsState(constraints, current, animate);
+  proxy_->UpdateBrowserControlsState(constraints, current, animate,
+                                     offset_tags_info);
 }
 
 void LayerTreeHost::AnimateLayers(base::TimeTicks monotonic_time) {

cc/trees/layer_tree_host.h

@@ -27,10 +27,12 @@
 #include "base/task/sequenced_task_runner.h"
 #include "base/task/single_thread_task_runner.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
 #include "cc/base/completion_event.h"
 #include "cc/benchmarks/micro_benchmark.h"
 #include "cc/benchmarks/micro_benchmark_controller.h"
 #include "cc/cc_export.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "cc/input/compositor_input_interfaces.h"
 #include "cc/input/event_listener_properties.h"
@@ -380,9 +382,11 @@ class CC_EXPORT LayerTreeHost : public MutatorHostClient {
   // Input Handling ---------------------------------------------
 
   // Sets the state of the browser controls. (Used for URL bar animations).
-  void UpdateBrowserControlsState(BrowserControlsState constraints,
-                                  BrowserControlsState current,
-                                  bool animate);
+  void UpdateBrowserControlsState(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info);
 
   // Returns the delegate that the input handler uses to communicate with the
   // LayerTreeHostImpl on the compositor thread. Must be dereferenced only on

cc/trees/layer_tree_host_impl.cc

@@ -41,6 +41,7 @@
 #include "base/time/time.h"
 #include "base/trace_event/traced_value.h"
 #include "base/trace_event/typed_macros.h"
+#include "base/types/optional_ref.h"
 #include "build/build_config.h"
 #include "build/chromeos_buildflags.h"
 #include "cc/base/devtools_instrumentation.h"
@@ -51,6 +52,7 @@
 #include "cc/benchmarks/benchmark_instrumentation.h"
 #include "cc/debug/rendering_stats_instrumentation.h"
 #include "cc/input/browser_controls_offset_manager.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/page_scale_animation.h"
 #include "cc/input/scrollbar_animation_controller.h"
 #include "cc/layers/append_quads_data.h"
@@ -354,9 +356,10 @@ void LayerTreeHostImpl::SetDeferBeginMainFrame(
 void LayerTreeHostImpl::UpdateBrowserControlsState(
     BrowserControlsState constraints,
     BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info) {
   browser_controls_offset_manager_->UpdateBrowserControlsState(
-      constraints, current, animate);
+      constraints, current, animate, offset_tags_info);
 }
 
 bool LayerTreeHostImpl::HasScrollLinkedAnimation(ElementId for_scroller) const {

cc/trees/layer_tree_host_impl.h

@@ -27,10 +27,12 @@
 #include "base/task/sequenced_task_runner.h"
 #include "base/task/single_thread_task_runner.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
 #include "cc/benchmarks/micro_benchmark_controller_impl.h"
 #include "cc/cc_export.h"
 #include "cc/input/actively_scrolling_type.h"
 #include "cc/input/browser_controls_offset_manager_client.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/input_handler.h"
 #include "cc/input/scrollbar_animation_controller.h"
 #include "cc/layers/layer_collections.h"
@@ -386,9 +388,12 @@ class CC_EXPORT LayerTreeHostImpl : public TileManagerClient,
   LayerTreeHostImpl& GetImplDeprecated() override;
   const LayerTreeHostImpl& GetImplDeprecated() const override;
   void SetDeferBeginMainFrame(bool defer_begin_main_frame) const override;
-  void UpdateBrowserControlsState(BrowserControlsState constraints,
-                                  BrowserControlsState current,
-                                  bool animate) override;
+  void UpdateBrowserControlsState(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info)
+      override;
   bool HasScrollLinkedAnimation(ElementId for_scroller) const override;
 
   void DetachInputDelegateAndRenderFrameObserver();

cc/trees/layer_tree_host_impl_unittest.cc

@@ -8178,7 +8178,8 @@ TEST_F(LayerTreeHostImplBrowserControlsTest,
 
   // Kick off an animation to show the browser controls.
   host_impl_->browser_controls_manager()->UpdateBrowserControlsState(
-      BrowserControlsState::kBoth, BrowserControlsState::kShown, true);
+      BrowserControlsState::kBoth, BrowserControlsState::kShown, true,
+      std::nullopt);
   base::TimeTicks start_time = base::TimeTicks::Now();
   viz::BeginFrameArgs begin_frame_args =
       viz::CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE, 0, 1);
@@ -12370,7 +12371,8 @@ TEST_F(LayerTreeHostImplWithBrowserControlsTest,
   UpdateDrawProperties(host_impl_->active_tree());
 
   host_impl_->browser_controls_manager()->UpdateBrowserControlsState(
-      BrowserControlsState::kBoth, BrowserControlsState::kShown, false);
+      BrowserControlsState::kBoth, BrowserControlsState::kShown, false,
+      std::nullopt);
   DrawFrame();
 
   // First, scroll just the browser controls and verify that the scroll
@@ -12452,7 +12454,8 @@ TEST_F(LayerTreeHostImplWithBrowserControlsTest,
   host_impl_->active_tree()->SetBrowserControlsParams(
       {top_controls_height_, 0, 0, 0, false, true});
   host_impl_->browser_controls_manager()->UpdateBrowserControlsState(
-      BrowserControlsState::kBoth, BrowserControlsState::kShown, false);
+      BrowserControlsState::kBoth, BrowserControlsState::kShown, false,
+      std::nullopt);
   DrawFrame();
 
   LayerImpl* viewport_layer = InnerViewportScrollLayer();
@@ -12499,7 +12502,8 @@ TEST_F(LayerTreeHostImplWithBrowserControlsTest,
   UpdateDrawProperties(host_impl_->active_tree());
 
   host_impl_->browser_controls_manager()->UpdateBrowserControlsState(
-      BrowserControlsState::kBoth, BrowserControlsState::kShown, false);
+      BrowserControlsState::kBoth, BrowserControlsState::kShown, false,
+      std::nullopt);
   DrawFrame();
 
   const float residue = 35;
@@ -12580,7 +12584,8 @@ TEST_F(LayerTreeHostImplWithBrowserControlsTest,
   UpdateDrawProperties(host_impl_->active_tree());
 
   host_impl_->browser_controls_manager()->UpdateBrowserControlsState(
-      BrowserControlsState::kBoth, BrowserControlsState::kShown, false);
+      BrowserControlsState::kBoth, BrowserControlsState::kShown, false,
+      std::nullopt);
   float initial_scroll_offset = 50;
   scroll_layer->layer_tree_impl()
       ->property_trees()
@@ -12664,7 +12669,8 @@ TEST_F(LayerTreeHostImplWithBrowserControlsTest,
   UpdateDrawProperties(host_impl_->active_tree());
 
   host_impl_->browser_controls_manager()->UpdateBrowserControlsState(
-      BrowserControlsState::kBoth, BrowserControlsState::kShown, false);
+      BrowserControlsState::kBoth, BrowserControlsState::kShown, false,
+      std::nullopt);
   DrawFrame();
 
   float offset = 50;

cc/trees/layer_tree_host_unittest_scroll.cc

@@ -2989,7 +2989,8 @@ class LayerTreeHostScrollTestViewportAbortedCommit
   void WillSendBeginMainFrameOnThread(LayerTreeHostImpl* host_impl) override {
     if (is_first_frame_) {
       host_impl->browser_controls_manager()->UpdateBrowserControlsState(
-          BrowserControlsState::kHidden, BrowserControlsState::kHidden, true);
+          BrowserControlsState::kHidden, BrowserControlsState::kHidden, true,
+          std::nullopt);
       bool changed_since_last_sync = false;
       BrowserControlsState permitted_constraint =
           host_impl->browser_controls_manager()->PullConstraintForMainThread(

cc/trees/proxy.h

@@ -10,7 +10,9 @@
 
 #include "base/threading/platform_thread.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
 #include "cc/cc_export.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "cc/trees/paint_holding_commit_trigger.h"
 #include "cc/trees/paint_holding_reason.h"
@@ -96,9 +98,12 @@ class CC_EXPORT Proxy {
   virtual void SetPaintWorkletLayerPainter(
       std::unique_ptr<PaintWorkletLayerPainter> painter) = 0;
 
-  virtual void UpdateBrowserControlsState(BrowserControlsState constraints,
-                                          BrowserControlsState current,
-                                          bool animate) = 0;
+  virtual void UpdateBrowserControlsState(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo>
+          offset_tags_info) = 0;
 
   virtual void RequestBeginMainFrameNotExpected(bool new_state) = 0;
 

cc/trees/proxy_impl.cc

@@ -20,10 +20,12 @@
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/traced_value.h"
 #include "base/trace_event/typed_macros.h"
+#include "base/types/optional_ref.h"
 #include "cc/base/devtools_instrumentation.h"
 #include "cc/base/features.h"
 #include "cc/benchmarks/benchmark_instrumentation.h"
 #include "cc/input/browser_controls_offset_manager.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/metrics/compositor_timing_history.h"
 #include "cc/paint/paint_worklet_layer_painter.h"
 #include "cc/trees/compositor_commit_data.h"
@@ -172,10 +174,11 @@ void ProxyImpl::InitializePaintWorkletLayerPainterOnImpl(
 void ProxyImpl::UpdateBrowserControlsStateOnImpl(
     BrowserControlsState constraints,
     BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info) {
   DCHECK(IsImplThread());
   host_impl_->browser_controls_manager()->UpdateBrowserControlsState(
-      constraints, current, animate);
+      constraints, current, animate, offset_tags_info);
 }
 
 void ProxyImpl::InitializeLayerTreeFrameSinkOnImpl(

cc/trees/proxy_impl.h

@@ -12,8 +12,10 @@
 #include "base/memory/raw_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/task/single_thread_task_runner.h"
+#include "base/types/optional_ref.h"
 #include "cc/base/completion_event.h"
 #include "cc/base/delayed_unique_notifier.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "cc/scheduler/scheduler.h"
 #include "cc/trees/layer_tree_host_impl.h"
@@ -45,9 +47,11 @@ class CC_EXPORT ProxyImpl : public LayerTreeHostImplClient,
 
   ProxyImpl& operator=(const ProxyImpl&) = delete;
 
-  void UpdateBrowserControlsStateOnImpl(BrowserControlsState constraints,
-                                        BrowserControlsState current,
-                                        bool animate);
+  void UpdateBrowserControlsStateOnImpl(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info);
   void InitializeLayerTreeFrameSinkOnImpl(
       LayerTreeFrameSink* layer_tree_frame_sink,
       base::WeakPtr<ProxyMain> proxy_main_frame_sink_bound_weak_ptr);

cc/trees/proxy_main.cc

@@ -16,10 +16,12 @@
 #include "base/synchronization/waitable_event.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/traced_value.h"
+#include "base/types/optional_ref.h"
 #include "cc/base/completion_event.h"
 #include "cc/base/devtools_instrumentation.h"
 #include "cc/base/features.h"
 #include "cc/benchmarks/benchmark_instrumentation.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/paint/paint_worklet_layer_painter.h"
 #include "cc/resources/ui_resource_manager.h"
 #include "cc/trees/latency_info_swap_promise.h"
@@ -821,14 +823,17 @@ void ProxyMain::ReleaseLayerTreeFrameSink() {
   completion.Wait();
 }
 
-void ProxyMain::UpdateBrowserControlsState(BrowserControlsState constraints,
-                                           BrowserControlsState current,
-                                           bool animate) {
+void ProxyMain::UpdateBrowserControlsState(
+    BrowserControlsState constraints,
+    BrowserControlsState current,
+    bool animate,
+    base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info) {
   DCHECK(IsMainThread());
   ImplThreadTaskRunner()->PostTask(
-      FROM_HERE, base::BindOnce(&ProxyImpl::UpdateBrowserControlsStateOnImpl,
-                                base::Unretained(proxy_impl_.get()),
-                                constraints, current, animate));
+      FROM_HERE,
+      base::BindOnce(&ProxyImpl::UpdateBrowserControlsStateOnImpl,
+                     base::Unretained(proxy_impl_.get()), constraints, current,
+                     animate, offset_tags_info));
 }
 
 void ProxyMain::RequestBeginMainFrameNotExpected(bool new_state) {

cc/trees/proxy_main.h

@@ -11,7 +11,9 @@
 #include "base/memory/raw_ptr.h"
 #include "base/task/single_thread_task_runner.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
 #include "cc/cc_export.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/paint_holding_reason.h"
@@ -115,9 +117,12 @@ class CC_EXPORT ProxyMain : public Proxy {
       std::unique_ptr<PaintWorkletLayerPainter> painter) override;
   bool MainFrameWillHappenForTesting() override;
   void ReleaseLayerTreeFrameSink() override;
-  void UpdateBrowserControlsState(BrowserControlsState constraints,
-                                  BrowserControlsState current,
-                                  bool animate) override;
+  void UpdateBrowserControlsState(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info)
+      override;
   void RequestBeginMainFrameNotExpected(bool new_state) override;
   void SetSourceURL(ukm::SourceId source_id, const GURL& url) override;
   void SetUkmSmoothnessDestination(

cc/trees/single_thread_proxy.cc

@@ -15,11 +15,13 @@
 #include "base/notreached.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/trace_event/trace_event.h"
+#include "base/types/optional_ref.h"
 #include "build/chromeos_buildflags.h"
 #include "cc/base/completion_event.h"
 #include "cc/base/devtools_instrumentation.h"
 #include "cc/benchmarks/benchmark_instrumentation.h"
 #include "cc/input/browser_controls_offset_manager.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/metrics/compositor_timing_history.h"
 #include "cc/paint/paint_worklet_layer_painter.h"
 #include "cc/resources/ui_resource_manager.h"
@@ -995,11 +997,12 @@ double SingleThreadProxy::GetPercentDroppedFrames() const {
 void SingleThreadProxy::UpdateBrowserControlsState(
     BrowserControlsState constraints,
     BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info) {
   DCHECK(task_runner_provider_->IsMainThread());
   DebugScopedSetImplThread impl(task_runner_provider_);
   host_impl_->browser_controls_manager()->UpdateBrowserControlsState(
-      constraints, current, animate);
+      constraints, current, animate, offset_tags_info);
 }
 
 bool SingleThreadProxy::WillBeginImplFrame(const viz::BeginFrameArgs& args) {

cc/trees/single_thread_proxy.h

@@ -13,6 +13,8 @@
 #include "base/containers/flat_set.h"
 #include "base/memory/raw_ptr.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/scheduler/scheduler.h"
 #include "cc/trees/layer_tree_host_impl.h"
 #include "cc/trees/paint_holding_reason.h"
@@ -86,9 +88,12 @@ class CC_EXPORT SingleThreadProxy : public Proxy,
                                    base::OnceClosure callback) override;
   double GetPercentDroppedFrames() const override;
 
-  void UpdateBrowserControlsState(BrowserControlsState constraints,
-                                  BrowserControlsState current,
-                                  bool animate) override;
+  void UpdateBrowserControlsState(
+      BrowserControlsState constraints,
+      BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const BrowserControlsOffsetTagsInfo> offset_tags_info)
+      override;
 
   // SchedulerClient implementation
   bool WillBeginImplFrame(const viz::BeginFrameArgs& args) override;

chrome/android/java/src/org/chromium/chrome/browser/tab/TabBrowserControlsConstraintsHelper.java

@@ -263,7 +263,8 @@ public class TabBrowserControlsConstraintsHelper implements UserData {
                         mTab.getWebContents(),
                         constraints,
                         current,
-                        animate);
+                        animate,
+                        new BrowserControlsOffsetTagsInfo(newTag));
 
         mTopControlsOffsetTag = newTag;
     }
@@ -290,6 +291,7 @@ public class TabBrowserControlsConstraintsHelper implements UserData {
                 WebContents webContents,
                 int contraints,
                 int current,
-                boolean animate);
+                boolean animate,
+                BrowserControlsOffsetTagsInfo offsetTagsInfo);
     }
 }

chrome/android/junit/src/org/chromium/chrome/browser/tab/TabBrowserControlsConstraintsHelperTest.java

@@ -156,7 +156,8 @@ public class TabBrowserControlsConstraintsHelperTest {
                         Mockito.any(),
                         Mockito.anyInt(),
                         Mockito.anyInt(),
-                        Mockito.anyBoolean());
+                        Mockito.anyBoolean(),
+                        Mockito.any());
     }
 
     @Test
@@ -209,7 +210,8 @@ public class TabBrowserControlsConstraintsHelperTest {
                         Mockito.same(mWebContents),
                         Mockito.eq(constraints),
                         Mockito.eq(current),
-                        Mockito.eq(animate));
+                        Mockito.eq(animate),
+                        Mockito.any());
         Mockito.clearInvocations(mJniMock);
     }
 

chrome/browser/android/DEPS

@@ -2,6 +2,7 @@ include_rules = [
   "-components/devtools_bridge",
   "+components/resources/android",
   "+cc/input/browser_controls_state.h",
+  "+cc/input/browser_controls_offset_tags_info.h",
   "+cc/slim/layer.h",
   "+chrome/android",
   "+chrome/browser/web_share_target",

chrome/browser/android/bottombar/overlay_panel_content.cc

@@ -166,7 +166,7 @@ void OverlayPanelContent::UpdateBrowserControlsState(
     state = cc::BrowserControlsState::kHidden;
 
   web_contents_->UpdateBrowserControlsState(
-      state, cc::BrowserControlsState::kBoth, false);
+      state, cc::BrowserControlsState::kBoth, false, std::nullopt);
 }
 
 jlong JNI_OverlayPanelContent_Init(JNIEnv* env,

chrome/browser/android/tab_browser_controls_constraints_helper.cc

@@ -4,6 +4,8 @@
 
 #include "chrome/browser/android/tab_browser_controls_constraints_helper.h"
 
+#include "cc/input/android/offset_tag_android.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "chrome/common/chrome_render_frame.mojom.h"
 #include "content/public/browser/render_frame_host.h"
@@ -36,7 +38,8 @@ void TabBrowserControlsConstraintsHelper::UpdateState(
     const JavaParamRef<jobject>& jweb_contents,
     jint constraints,
     jint current,
-    jboolean animate) {
+    jboolean animate,
+    const JavaParamRef<jobject>& joffset_tags_info) {
   cc::BrowserControlsState constraints_state =
       static_cast<cc::BrowserControlsState>(constraints);
   cc::BrowserControlsState current_state =
@@ -47,8 +50,12 @@ void TabBrowserControlsConstraintsHelper::UpdateState(
     return;
   }
 
+  cc::BrowserControlsOffsetTagsInfo offset_tags_info =
+      cc::android::FromJavaBrowserControlsOffsetTagsInfo(env,
+                                                         joffset_tags_info);
+
   web_contents->UpdateBrowserControlsState(constraints_state, current_state,
-                                           animate);
+                                           animate, offset_tags_info);
 }
 
 static jlong JNI_TabBrowserControlsConstraintsHelper_Init(

chrome/browser/android/tab_browser_controls_constraints_helper.h

@@ -15,12 +15,14 @@ class TabBrowserControlsConstraintsHelper {
       const base::android::JavaParamRef<jobject>& obj);
   ~TabBrowserControlsConstraintsHelper();
 
-  void UpdateState(JNIEnv* env,
-                   const base::android::JavaParamRef<jobject>& obj,
-                   const base::android::JavaParamRef<jobject>& jweb_contents,
-                   jint constraints,
-                   jint current,
-                   jboolean animate);
+  void UpdateState(
+      JNIEnv* env,
+      const base::android::JavaParamRef<jobject>& obj,
+      const base::android::JavaParamRef<jobject>& jweb_contents,
+      jint constraints,
+      jint current,
+      jboolean animate,
+      const base::android::JavaParamRef<jobject>& joffset_tags_info);
   void OnDestroyed(JNIEnv* env,
                    const base::android::JavaParamRef<jobject>& obj);
 

chrome/browser/ui/views/frame/top_controls_slide_controller_chromeos.cc

@@ -592,7 +592,7 @@ void TopControlsSlideControllerChromeOS::UpdateBrowserControlsStateShown(
   const cc::BrowserControlsState current_state =
       cc::BrowserControlsState::kShown;
   web_contents->UpdateBrowserControlsState(constraints_state, current_state,
-                                           animate);
+                                           animate, std::nullopt);
 }
 
 bool TopControlsSlideControllerChromeOS::CanEnable(

components/thin_webview/internal/thin_webview.cc

@@ -53,7 +53,7 @@ void ThinWebView::PrimaryPageChanged(content::Page& page) {
   // Disable browser controls when used for thin webview.
   web_contents_->UpdateBrowserControlsState(cc::BrowserControlsState::kHidden,
                                             cc::BrowserControlsState::kHidden,
-                                            false);
+                                            false, std::nullopt);
 }
 
 void ThinWebView::SetWebContents(

content/browser/renderer_host/back_forward_cache_impl.cc

@@ -331,7 +331,7 @@ void RestoreBrowserControlsState(RenderFrameHostImpl* cached_rfh) {
     cached_rfh->GetPage().UpdateBrowserControlsState(
         cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kHidden,
         // Do not animate as we want this to happen "instantaneously"
-        false);
+        false, std::nullopt);
   }
 }
 

content/browser/renderer_host/page_impl.cc

@@ -9,6 +9,7 @@
 #include "base/i18n/character_encoding.h"
 #include "base/trace_event/optional_trace_event.h"
 #include "cc/base/features.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "content/browser/manifest/manifest_manager_host.h"
 #include "content/browser/renderer_host/frame_tree_node.h"
 #include "content/browser/renderer_host/page_delegate.h"
@@ -21,6 +22,7 @@
 #include "content/public/browser/peak_gpu_memory_tracker.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/common/content_client.h"
+#include "services/viz/public/mojom/compositing/offset_tag.mojom.h"
 #include "third_party/blink/public/common/features.h"
 #include "third_party/blink/public/common/loader/loader_constants.h"
 #include "third_party/blink/public/common/shared_storage/shared_storage_utils.h"
@@ -321,9 +323,11 @@ RenderFrameHostImpl& PageImpl::GetMainDocument() const {
   return *main_document_;
 }
 
-void PageImpl::UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                          cc::BrowserControlsState current,
-                                          bool animate) {
+void PageImpl::UpdateBrowserControlsState(
+    cc::BrowserControlsState constraints,
+    cc::BrowserControlsState current,
+    bool animate,
+    const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info) {
   // TODO(crbug.com/40159655): Asking for the LocalMainFrame interface
   // before the RenderFrame is created is racy.
   if (!GetMainDocument().IsRenderFrameLive())
@@ -332,10 +336,10 @@ void PageImpl::UpdateBrowserControlsState(cc::BrowserControlsState constraints,
   if (base::FeatureList::IsEnabled(
           features::kUpdateBrowserControlsWithoutProxy)) {
     GetMainDocument().GetRenderWidgetHost()->UpdateBrowserControlsState(
-        constraints, current, animate);
+        constraints, current, animate, offset_tags_info);
   } else {
     GetMainDocument().GetAssociatedLocalMainFrame()->UpdateBrowserControlsState(
-        constraints, current, animate);
+        constraints, current, animate, offset_tags_info);
   }
 }
 

content/browser/renderer_host/page_impl.h

@@ -13,6 +13,7 @@
 #include "base/memory/raw_ref.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "content/browser/fenced_frame/fenced_frame_url_mapping.h"
 #include "content/browser/renderer_host/stored_page.h"
@@ -172,9 +173,11 @@ class CONTENT_EXPORT PageImpl : public Page {
   // Hide or show the browser controls for the given Page, based on allowed
   // states, desired state and whether the transition should be animated or
   // not.
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate);
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info);
 
   float GetPageScaleFactor() const;
 

content/browser/renderer_host/render_widget_host_impl.cc

@@ -41,6 +41,7 @@
 #include "base/trace_event/trace_event.h"
 #include "build/build_config.h"
 #include "cc/base/switches.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/trees/browser_controls_params.h"
 #include "cc/trees/render_frame_metadata.h"
 #include "components/input/native_web_keyboard_event.h"
@@ -2683,9 +2684,10 @@ SiteInstanceGroup* RenderWidgetHostImpl::GetSiteInstanceGroup() {
 void RenderWidgetHostImpl::UpdateBrowserControlsState(
     cc::BrowserControlsState constraints,
     cc::BrowserControlsState current,
-    bool animate) {
-  GetWidgetInputHandler()->UpdateBrowserControlsState(constraints, current,
-                                                      animate);
+    bool animate,
+    const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info) {
+  GetWidgetInputHandler()->UpdateBrowserControlsState(
+      constraints, current, animate, offset_tags_info);
 }
 
 void RenderWidgetHostImpl::StartDragging(

content/browser/renderer_host/render_widget_host_impl.h

@@ -31,6 +31,7 @@
 #include "base/timer/timer.h"
 #include "base/types/pass_key.h"
 #include "build/build_config.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/mojom/render_frame_metadata.mojom.h"
 #include "components/input/event_with_latency_info.h"
 #include "components/viz/common/surfaces/frame_sink_id.h"
@@ -932,9 +933,11 @@ class CONTENT_EXPORT RenderWidgetHostImpl
   SiteInstanceGroup* GetSiteInstanceGroup();
 
   // Updates the browser controls by directly IPCing onto the compositor thread.
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate);
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info);
 
   void StartDragging(blink::mojom::DragDataPtr drag_data,
                      const url::Origin& source_origin,

content/browser/web_contents/web_contents_impl.cc

@@ -49,6 +49,7 @@
 #include "base/trace_event/trace_event.h"
 #include "build/build_config.h"
 #include "build/chromeos_buildflags.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "components/attribution_reporting/features.h"
 #include "components/download/public/common/download_stats.h"
 #include "components/url_formatter/url_formatter.h"
@@ -10786,10 +10787,12 @@ void WebContentsImpl::NotifyPrimaryMainFrameProcessIsAlive() {
 void WebContentsImpl::UpdateBrowserControlsState(
     cc::BrowserControlsState constraints,
     cc::BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info) {
   // Browser controls should be synchronised with the scroll state. Therefore,
   // they are controlled from the renderer by the main RenderFrame(Host).
-  GetPrimaryPage().UpdateBrowserControlsState(constraints, current, animate);
+  GetPrimaryPage().UpdateBrowserControlsState(constraints, current, animate,
+                                              offset_tags_info);
 }
 
 void WebContentsImpl::SetV8CompileHints(base::ReadOnlySharedMemoryRegion data) {

content/browser/web_contents/web_contents_impl.h

@@ -29,6 +29,7 @@
 #include "base/scoped_observation.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "components/download/public/common/download_url_parameters.h"
 #include "content/browser/media/audio_stream_monitor.h"
 #include "content/browser/media/forwarding_audio_stream_factory.h"
@@ -602,9 +603,12 @@ class CONTENT_EXPORT WebContentsImpl
   const base::Location& GetCreatorLocation() override;
   const std::optional<blink::mojom::PictureInPictureWindowOptions>&
   GetPictureInPictureOptions() const override;
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate) override;
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info)
+      override;
   void SetV8CompileHints(base::ReadOnlySharedMemoryRegion data) override;
   void SetTabSwitchStartTime(base::TimeTicks start_time,
                              bool destination_is_loaded) override;

content/common/input/render_input_router.cc

@@ -12,6 +12,7 @@
 #include "base/lazy_instance.h"
 #include "base/location.h"
 #include "base/memory/ptr_util.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "content/common/input/input_router_config_helper.h"
 #include "content/common/input/render_widget_host_input_event_router.h"
 #include "content/common/input/render_widget_host_view_input.h"
@@ -93,9 +94,12 @@ class UnboundWidgetInputHandler : public blink::mojom::WidgetInputHandler {
           request) override {
     NOTREACHED_IN_MIGRATION() << "Input request on unbound interface";
   }
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate) override {
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info)
+      override {
     NOTREACHED_IN_MIGRATION() << "Input request on unbound interface";
   }
 };

content/public/browser/web_contents.h

@@ -25,6 +25,7 @@
 #include "base/supports_user_data.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/invalidate_type.h"
@@ -1431,9 +1432,12 @@ class WebContents : public PageNavigator,
   // Hide or show the browser controls for the given WebContents, based on
   // allowed states, desired state and whether the transition should be animated
   // or not.
-  virtual void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                          cc::BrowserControlsState current,
-                                          bool animate) = 0;
+  virtual void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      const std::optional<cc::BrowserControlsOffsetTagsInfo>&
+          offset_tags_info) = 0;
 
   // Transmits data to V8CrowdsourcedCompileHintsConsumer in the renderer. The
   // data is a model describing which JavaScript functions on the page should be

content/renderer/gpu_benchmarking_extension.cc

@@ -1225,7 +1225,7 @@ void GpuBenchmarking::SetBrowserControlsShown(bool show) {
       cc::BrowserControlsState::kBoth,
       show ? cc::BrowserControlsState::kShown
            : cc::BrowserControlsState::kHidden,
-      false);
+      false, std::nullopt);
 }
 
 float GpuBenchmarking::VisualViewportY() {

content/test/mock_widget_input_handler.cc

@@ -6,6 +6,7 @@
 
 #include "base/run_loop.h"
 #include "build/build_config.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/blink/public/common/input/web_gesture_event.h"
 #include "third_party/blink/public/common/input/web_mouse_event.h"
@@ -140,7 +141,8 @@ void MockWidgetInputHandler::GetFrameWidgetInputHandler(
 void MockWidgetInputHandler::UpdateBrowserControlsState(
     cc::BrowserControlsState constraints,
     cc::BrowserControlsState current,
-    bool animate) {}
+    bool animate,
+    const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info) {}
 
 MockWidgetInputHandler::DispatchedMessage::DispatchedMessage(
     const std::string& name)

content/test/mock_widget_input_handler.h

@@ -11,6 +11,7 @@
 #include <utility>
 
 #include "build/build_config.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "mojo/public/cpp/bindings/receiver.h"
 #include "mojo/public/cpp/bindings/remote.h"
 #include "third_party/blink/public/mojom/input/input_handler.mojom.h"
@@ -276,9 +277,12 @@ class MockWidgetInputHandler : public blink::mojom::WidgetInputHandler {
   void GetFrameWidgetInputHandler(
       mojo::PendingAssociatedReceiver<blink::mojom::FrameWidgetInputHandler>
           interface_request) override;
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate) override;
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info)
+      override;
 
   using MessageVector = std::vector<std::unique_ptr<DispatchedMessage>>;
   MessageVector GetAndResetDispatchedMessages();

content/web_test/browser/web_test_control_host.cc

@@ -616,8 +616,8 @@ void WebTestControlHost::PrepareForWebTest(const TestInfo& test_info) {
   // TODO(danakj): We no longer run web tests on android, and this is an android
   // feature, so maybe this isn't needed anymore.
   main_window_->web_contents()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kHidden,
-      false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kHidden, false,
+      std::nullopt);
 
   // We did not track the |main_window_| RenderFrameHost during the creation of
   // |main_window_|, since we need the pointer value in this class set first. So

third_party/blink/public/mojom/frame/frame.mojom

@@ -5,6 +5,7 @@
 module blink.mojom;
 
 import "cc/mojom/browser_controls_state.mojom";
+import "cc/mojom/browser_controls_offset_tags_info.mojom";
 import "mojo/public/mojom/base/byte_string.mojom";
 import "mojo/public/mojom/base/shared_memory.mojom";
 import "mojo/public/mojom/base/string16.mojom";
@@ -20,6 +21,7 @@ import "services/network/public/mojom/network_types.mojom";
 import "services/network/public/mojom/source_location.mojom";
 import "services/network/public/mojom/url_loader_completion_status.mojom";
 import "services/network/public/mojom/attribution.mojom";
+import "services/viz/public/mojom/compositing/offset_tag.mojom";
 import "skia/public/mojom/bitmap.mojom";
 import "skia/public/mojom/skcolor.mojom";
 import "skia/public/mojom/skcolor4f.mojom";
@@ -1219,9 +1221,27 @@ interface LocalMainFrame {
   // Notifies the renderer whether hiding/showing the browser controls is
   // enabled, what the current state should be, and whether or not to
   // animate to the proper state.
-  UpdateBrowserControlsState(cc.mojom.BrowserControlsState constraints,
-                             cc.mojom.BrowserControlsState current,
-                             bool animate);
+  //
+  // offset_tags_info consists of OffsetTags, and metadata for creating
+  // OffsetTagConstraints. It is passed to the renderer and used to tag the
+  // browser controls scroll offsets in the compositor frame's metadata, with
+  // the goal of allowing viz to scroll the top controls by applying the
+  // offset. The slim::Layers for the top controls in the browser must be
+  // tagged with the same token.
+  // A zero token is passed when the browser is forcing the controls to be
+  // shown/hidden. When this happens, the browser process will have removed
+  // the renderer's OffsetTagDefinition from the associated SurfaceLayer, so
+  // viz will not look for scroll offsets or OffsetTags in the compositor frame
+  // metadata anymore. The renderer should also not tag any scroll offsets with
+  // OffsetTags, as they won't be seen by viz.
+  // A null token is passed when scrolling top controls is viz is not
+  // applicable (ex. chromeos, UI elements that overlay on top of chrome,
+  // tests, etc.)
+  UpdateBrowserControlsState(
+      cc.mojom.BrowserControlsState constraints,
+      cc.mojom.BrowserControlsState current,
+      bool animate,
+      cc.mojom.BrowserControlsOffsetTagsInfo? offset_tags_info);
 
   // Transmits data to V8CrowdsourcedCompileHintsConsumer in the renderer. The
   // data is a Bloom filter describing which JavaScript functions on the page

third_party/blink/public/mojom/input/input_handler.mojom

@@ -4,6 +4,7 @@
 
 module blink.mojom;
 
+import "cc/mojom/browser_controls_offset_tags_info.mojom";
 import "cc/mojom/browser_controls_state.mojom";
 import "cc/mojom/overscroll_behavior.mojom";
 import "cc/mojom/touch_action.mojom";
@@ -529,10 +530,9 @@ interface WidgetInputHandler {
   GetFrameWidgetInputHandler(
       pending_associated_receiver<FrameWidgetInputHandler> interface_request);
 
-  // Notifies the renderer whether hiding/showing the browser controls is
-  // enabled, what the current state should be, and whether or not to
-  // animate to the proper state.
+  // see UpdateBrowserControlsState in third_party/blink/public/mojom/frame/frame.mojom for details
   UpdateBrowserControlsState(cc.mojom.BrowserControlsState constraints,
                              cc.mojom.BrowserControlsState current,
-                             bool animate);
+                             bool animate,
+                             cc.mojom.BrowserControlsOffsetTagsInfo? offset_tags_info);
 };

third_party/blink/renderer/core/frame/DEPS

@@ -1,3 +1,7 @@
+include_rules = {
+  "+cc/input/browser_controls_offset_tags_info.h",
+}
+
 specific_include_rules = {
   "ad_tracker_test\.cc": [
     "+base/run_loop.h",

third_party/blink/renderer/core/frame/browser_controls_test.cc

@@ -199,7 +199,7 @@ class BrowserControlsSimTest : public SimTest {
     WebView().SetDefaultPageScaleLimits(0.25f, 5);
     Compositor().LayerTreeHost()->UpdateBrowserControlsState(
         cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown,
-        false);
+        false, std::nullopt);
     WebView().ResizeWithBrowserControls(gfx::Size(412, 604), 56.f, 50.f, true);
   }
 
@@ -857,8 +857,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(StateConstraints)) {
   // Setting permitted state should change the content offset to match the
   // constraint.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kShown, cc::BrowserControlsState::kShown,
-      false);
+      cc::BrowserControlsState::kShown, cc::BrowserControlsState::kShown, false,
+      std::nullopt);
   Compositor().BeginFrame();
   EXPECT_FLOAT_EQ(50.f, WebView().GetBrowserControls().ContentOffset());
 
@@ -877,7 +877,7 @@ TEST_F(BrowserControlsSimTest, MAYBE(StateConstraints)) {
   // constraint.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
       cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kHidden,
-      false);
+      false, std::nullopt);
   Compositor().BeginFrame();
   EXPECT_FLOAT_EQ(0, WebView().GetBrowserControls().ContentOffset());
 
@@ -889,7 +889,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(StateConstraints)) {
 
   // Setting permitted state to "both" should not change content offset.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kBoth, false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   Compositor().BeginFrame();
   EXPECT_FLOAT_EQ(0, WebView().GetBrowserControls().ContentOffset());
 
@@ -919,19 +920,21 @@ TEST_F(BrowserControlsSimTest, MAYBE(StateConstraints)) {
 
   EXPECT_FLOAT_EQ(0, WebView().GetBrowserControls().ContentOffset());
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kBoth, false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   Compositor().BeginFrame();
   EXPECT_FLOAT_EQ(0, WebView().GetBrowserControls().ContentOffset());
 
   // Setting just the constraint should affect the content offset.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth,
-      false);
+      cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   Compositor().BeginFrame();
   EXPECT_FLOAT_EQ(0, WebView().GetBrowserControls().ContentOffset());
 
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kShown, cc::BrowserControlsState::kBoth, false);
+      cc::BrowserControlsState::kShown, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   Compositor().BeginFrame();
   EXPECT_FLOAT_EQ(50, WebView().GetBrowserControls().ContentOffset());
 }
@@ -1015,7 +1018,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectLayoutHeightWhenConstrained)) {
 
   WebView().ResizeWithBrowserControls(gfx::Size(400, 300), 100.f, 0, true);
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown, false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown, false,
+      std::nullopt);
   Compositor().BeginFrame();
 
   Element* abs_pos = GetDocument().getElementById(WebString::FromUTF8("abs"));
@@ -1033,8 +1037,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectLayoutHeightWhenConstrained)) {
   // Now lock the controls in a hidden state. The layout and elements should
   // resize without a WebView::resize.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth,
-      false);
+      cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   Compositor().BeginFrame();
 
   EXPECT_FLOAT_EQ(200.f, abs_pos->GetBoundingClientRect()->height());
@@ -1045,7 +1049,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectLayoutHeightWhenConstrained)) {
   // Unlock the controls, the sizes should change even though the controls are
   // still hidden.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kBoth, false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   Compositor().BeginFrame();
 
   EXPECT_FLOAT_EQ(150.f, abs_pos->GetBoundingClientRect()->height());
@@ -1055,7 +1060,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectLayoutHeightWhenConstrained)) {
 
   // Now lock the controls in a shown state.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kShown, cc::BrowserControlsState::kBoth, false);
+      cc::BrowserControlsState::kShown, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   WebView().ResizeWithBrowserControls(gfx::Size(400, 300), 100.f, 0, true);
   Compositor().BeginFrame();
 
@@ -1067,8 +1073,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectLayoutHeightWhenConstrained)) {
   // Shown -> Hidden
   WebView().ResizeWithBrowserControls(gfx::Size(400, 400), 100.f, 0, false);
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth,
-      false);
+      cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   Compositor().BeginFrame();
 
   EXPECT_FLOAT_EQ(200.f, abs_pos->GetBoundingClientRect()->height());
@@ -1079,7 +1085,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectLayoutHeightWhenConstrained)) {
   // Go from Unlocked and showing, to locked and hidden but issue the resize
   // before the constraint update to check for race issues.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown, false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown, false,
+      std::nullopt);
   WebView().ResizeWithBrowserControls(gfx::Size(400, 300), 100.f, 0, true);
   Compositor().BeginFrame();
   ASSERT_EQ(300, GetDocument().GetFrame()->View()->GetLayoutSize().height());
@@ -1087,7 +1094,7 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectLayoutHeightWhenConstrained)) {
   WebView().ResizeWithBrowserControls(gfx::Size(400, 400), 100.f, 0, false);
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
       cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kHidden,
-      false);
+      false, std::nullopt);
   Compositor().BeginFrame();
 
   EXPECT_FLOAT_EQ(200.f, abs_pos->GetBoundingClientRect()->height());
@@ -1120,7 +1127,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectViewportConstrainedSticky)) {
 
   WebView().ResizeWithBrowserControls(gfx::Size(400, 300), 100.f, 0, true);
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown, false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown, false,
+      std::nullopt);
   Compositor().BeginFrame();
 
   Element* sticky_pos =
@@ -1139,8 +1147,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectViewportConstrainedSticky)) {
   // Now lock the controls in a hidden state. The layout and elements should
   // resize without a WebView::resize.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth,
-      false);
+      cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   Compositor().BeginFrame();
   EXPECT_EQ(400, GetDocument().GetFrame()->View()->GetLayoutSize().height());
   EXPECT_FLOAT_EQ(400.f, sticky_pos->GetBoundingClientRect()->bottom());
@@ -1148,14 +1156,16 @@ TEST_F(BrowserControlsSimTest, MAYBE(AffectViewportConstrainedSticky)) {
   // Unlock the controls, the sizes should change even though the controls are
   // still hidden.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kBoth, false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   Compositor().BeginFrame();
   EXPECT_EQ(300, GetDocument().GetFrame()->View()->GetLayoutSize().height());
   EXPECT_FLOAT_EQ(400.f, sticky_pos->GetBoundingClientRect()->bottom());
 
   // Now lock the controls in a shown state.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kShown, cc::BrowserControlsState::kBoth, false);
+      cc::BrowserControlsState::kShown, cc::BrowserControlsState::kBoth, false,
+      std::nullopt);
   WebView().ResizeWithBrowserControls(gfx::Size(400, 300), 100.f, 0, true);
   Compositor().BeginFrame();
   EXPECT_EQ(300, GetDocument().GetFrame()->View()->GetLayoutSize().height());
@@ -1649,7 +1659,8 @@ TEST_F(BrowserControlsSimTest, MAYBE(ViewportUnitsWhenControlsLocked)) {
       )HTML");
   WebView().ResizeWithBrowserControls(gfx::Size(400, 300), 100.f, 0, true);
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown, false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown, false,
+      std::nullopt);
   Compositor().BeginFrame();
 
   ASSERT_EQ(1.f, WebView().GetBrowserControls().TopShownRatio());
@@ -1663,7 +1674,7 @@ TEST_F(BrowserControlsSimTest, MAYBE(ViewportUnitsWhenControlsLocked)) {
   {
     Compositor().LayerTreeHost()->UpdateBrowserControlsState(
         cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kHidden,
-        false);
+        false, std::nullopt);
     WebView().ResizeWithBrowserControls(gfx::Size(400, 400), 100.f, 0, false);
     Compositor().BeginFrame();
 
@@ -1685,7 +1696,7 @@ TEST_F(BrowserControlsSimTest, MAYBE(ViewportUnitsWhenControlsLocked)) {
   {
     Compositor().LayerTreeHost()->UpdateBrowserControlsState(
         cc::BrowserControlsState::kShown, cc::BrowserControlsState::kShown,
-        false);
+        false, std::nullopt);
     WebView().ResizeWithBrowserControls(gfx::Size(400, 300), 100.f, 0, true);
     Compositor().BeginFrame();
 
@@ -1893,12 +1904,12 @@ TEST_F(BrowserControlsSimTest, MixAnimatedAndNonAnimatedUpdateState) {
   // Kick off a non-animated clamp to hide the top controls.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
       cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth,
-      false /* animated */);
+      false /* animated */, std::nullopt);
 
   // Now kick off an animated one to do the same thing.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
       cc::BrowserControlsState::kHidden, cc::BrowserControlsState::kBoth,
-      true /* animated */);
+      true /* animated */, std::nullopt);
 
   // Advance time. In https://crbug.com/861618, the animation didn't realize
   // yet we're already at 0, so it would play the compositor-side up to 80ms,
@@ -1941,7 +1952,7 @@ TEST_F(BrowserControlsSimTest, HideAnimated) {
   // Kick off an animated hide.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
       cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kHidden,
-      true /* animated */);
+      true /* animated */, std::nullopt);
 
   Compositor().BeginFrame();
 
@@ -1974,8 +1985,8 @@ TEST_F(BrowserControlsSimTest, ShowAnimated) {
   Compositor().BeginFrame();
 
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kHidden,
-      false);
+      cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kHidden, false,
+      std::nullopt);
 
   Compositor().BeginFrame();
 
@@ -1985,7 +1996,7 @@ TEST_F(BrowserControlsSimTest, ShowAnimated) {
   // Kick off an animated show.
   Compositor().LayerTreeHost()->UpdateBrowserControlsState(
       cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown,
-      true /* animated */);
+      true /* animated */, std::nullopt);
 
   Compositor().BeginFrame();
 
@@ -2041,7 +2052,7 @@ TEST_F(BrowserControlsSimTest, ConstraintDoesntClampRatioInBlink) {
     // actually cause the controls to hide when we commit.
     Compositor().LayerTreeHost()->UpdateBrowserControlsState(
         cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kHidden,
-        false /* animated */);
+        false /* animated */, std::nullopt);
     Compositor().BeginFrame();
 
     EXPECT_EQ(0.f, WebView().GetBrowserControls().TopShownRatio());
@@ -2064,7 +2075,7 @@ TEST_F(BrowserControlsSimTest, ConstraintDoesntClampRatioInBlink) {
     // actually cause the controls to hide when we commit.
     Compositor().LayerTreeHost()->UpdateBrowserControlsState(
         cc::BrowserControlsState::kBoth, cc::BrowserControlsState::kShown,
-        false /* animated */);
+        false /* animated */, std::nullopt);
     Compositor().BeginFrame();
 
     EXPECT_EQ(1.f, WebView().GetBrowserControls().TopShownRatio());

third_party/blink/renderer/core/frame/local_frame_mojo_handler.cc

@@ -8,6 +8,7 @@
 #include "base/numerics/safe_conversions.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "services/network/public/cpp/url_loader_completion_status.h"
 #include "services/network/public/mojom/url_response_head.mojom.h"
 #include "third_party/blink/public/common/associated_interfaces/associated_interface_provider.h"
@@ -1302,7 +1303,8 @@ void LocalFrameMojoHandler::InstallCoopAccessMonitor(
 void LocalFrameMojoHandler::UpdateBrowserControlsState(
     cc::BrowserControlsState constraints,
     cc::BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info) {
   DCHECK(frame_->IsOutermostMainFrame());
   TRACE_EVENT2("renderer", "LocalFrame::UpdateBrowserControlsState",
                "Constraint", static_cast<int>(constraints), "Current",
@@ -1310,8 +1312,8 @@ void LocalFrameMojoHandler::UpdateBrowserControlsState(
   TRACE_EVENT_INSTANT1("renderer", "is_animated", TRACE_EVENT_SCOPE_THREAD,
                        "animated", animate);
 
-  frame_->GetWidgetForLocalRoot()->UpdateBrowserControlsState(constraints,
-                                                              current, animate);
+  frame_->GetWidgetForLocalRoot()->UpdateBrowserControlsState(
+      constraints, current, animate, offset_tags_info);
 }
 
 void LocalFrameMojoHandler::SetV8CompileHints(

third_party/blink/renderer/core/frame/local_frame_mojo_handler.h

@@ -6,6 +6,7 @@
 #define THIRD_PARTY_BLINK_RENDERER_CORE_FRAME_LOCAL_FRAME_MOJO_HANDLER_H_
 
 #include "build/build_config.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "third_party/blink/public/common/tokens/tokens.h"
 #include "third_party/blink/public/mojom/device_posture/device_posture_provider.mojom-blink.h"
 #include "third_party/blink/public/mojom/frame/back_forward_cache_controller.mojom-blink.h"
@@ -253,9 +254,12 @@ class LocalFrameMojoHandler
       network::mojom::blink::CrossOriginOpenerPolicyReporterParamsPtr
           coop_reporter_params,
       bool is_in_same_virtual_coop_related_group) final;
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate) override;
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info)
+      override;
 
   void SetV8CompileHints(base::ReadOnlySharedMemoryRegion data) override;
 

third_party/blink/renderer/core/frame/web_frame_widget_impl.cc

@@ -42,9 +42,11 @@
 #include "base/numerics/safe_conversions.h"
 #include "base/task/single_thread_task_runner.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
 #include "build/build_config.h"
 #include "cc/animation/animation_host.h"
 #include "cc/base/features.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/trees/compositor_commit_data.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/swap_promise.h"
@@ -1901,10 +1903,12 @@ const cc::LayerTreeSettings* WebFrameWidgetImpl::GetLayerTreeSettings() {
 void WebFrameWidgetImpl::UpdateBrowserControlsState(
     cc::BrowserControlsState constraints,
     cc::BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    base::optional_ref<const cc::BrowserControlsOffsetTagsInfo>
+        offset_tags_info) {
   DCHECK(View()->does_composite());
-  widget_base_->LayerTreeHost()->UpdateBrowserControlsState(constraints,
-                                                            current, animate);
+  widget_base_->LayerTreeHost()->UpdateBrowserControlsState(
+      constraints, current, animate, offset_tags_info);
 }
 
 void WebFrameWidgetImpl::SetHaveScrollEventHandlers(bool has_handlers) {

third_party/blink/renderer/core/frame/web_frame_widget_impl.h

@@ -35,9 +35,11 @@
 #include "base/memory/weak_ptr.h"
 #include "base/task/single_thread_task_runner.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
 #include "base/types/pass_key.h"
 #include "base/unguessable_token.h"
 #include "build/build_config.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/event_listener_properties.h"
 #include "cc/input/overscroll_behavior.h"
 #include "cc/trees/layer_tree_host.h"
@@ -235,9 +237,12 @@ class CORE_EXPORT WebFrameWidgetImpl
   void RequestBeginMainFrameNotExpected(bool request) final;
   int GetLayerTreeId() final;
   const cc::LayerTreeSettings* GetLayerTreeSettings() final;
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate) final;
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const cc::BrowserControlsOffsetTagsInfo>
+          offset_tags_info) final;
   void SetEventListenerProperties(cc::EventListenerClass,
                                   cc::EventListenerProperties) final;
   cc::EventListenerProperties EventListenerProperties(

third_party/blink/renderer/platform/widget/frame_widget.h

@@ -8,6 +8,8 @@
 #include <optional>
 
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "mojo/public/mojom/base/text_direction.mojom-blink.h"
 #include "services/viz/public/mojom/compositing/frame_sink_id.mojom-blink.h"
 #include "third_party/blink/public/mojom/input/input_handler.mojom-blink.h"
@@ -104,9 +106,12 @@ class PLATFORM_EXPORT FrameWidget {
   virtual const cc::LayerTreeSettings* GetLayerTreeSettings() = 0;
 
   // Sets the state of the browser controls. (Used for URL bar animations.)
-  virtual void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                          cc::BrowserControlsState current,
-                                          bool animate) = 0;
+  virtual void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const cc::BrowserControlsOffsetTagsInfo>
+          offset_tags_info) = 0;
 
   // Set or get what event handlers exist in the document contained in the
   // WebWidget in order to inform the compositor thread if it is able to handle

third_party/blink/renderer/platform/widget/input/input_handler_proxy.cc

@@ -20,8 +20,10 @@
 #include "base/task/single_thread_task_runner.h"
 #include "base/time/default_tick_clock.h"
 #include "base/trace_event/trace_event.h"
+#include "base/types/optional_ref.h"
 #include "build/build_config.h"
 #include "cc/base/features.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/main_thread_scrolling_reason.h"
 #include "cc/metrics/event_metrics.h"
 #include "cc/trees/latency_info_swap_promise_monitor.h"
@@ -1592,9 +1594,12 @@ void InputHandlerProxy::RequestAnimationForSnapFling() {
 void InputHandlerProxy::UpdateBrowserControlsState(
     cc::BrowserControlsState constraints,
     cc::BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    base::optional_ref<const cc::BrowserControlsOffsetTagsInfo>
+        offset_tags_info) {
   DCHECK(input_handler_);
-  input_handler_->UpdateBrowserControlsState(constraints, current, animate);
+  input_handler_->UpdateBrowserControlsState(constraints, current, animate,
+                                             offset_tags_info);
 }
 
 void InputHandlerProxy::FlushQueuedEventsForTesting() {

third_party/blink/renderer/platform/widget/input/input_handler_proxy.h

@@ -9,6 +9,8 @@
 
 #include "base/memory/raw_ptr.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "cc/input/input_handler.h"
 #include "cc/input/snap_fling_controller.h"
@@ -240,9 +242,12 @@ class PLATFORM_EXPORT InputHandlerProxy : public cc::InputHandlerClient,
   void ScrollEndForSnapFling(bool did_finish) override;
   void RequestAnimationForSnapFling() override;
 
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate);
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const cc::BrowserControlsOffsetTagsInfo>
+          offset_tags_info);
 
   bool gesture_scroll_on_impl_thread_for_testing() const {
     return handling_gesture_on_impl_thread_;

third_party/blink/renderer/platform/widget/input/input_handler_proxy_unittest.cc

@@ -16,8 +16,10 @@
 #include "base/test/simple_test_tick_clock.h"
 #include "base/test/task_environment.h"
 #include "base/test/trace_event_analyzer.h"
+#include "base/types/optional_ref.h"
 #include "build/build_config.h"
 #include "cc/base/features.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/main_thread_scrolling_reason.h"
 #include "cc/test/fake_impl_task_runner_provider.h"
 #include "cc/test/fake_layer_tree_host_impl.h"
@@ -117,9 +119,12 @@ class FakeCompositorDelegateForInput : public cc::CompositorDelegateForInput {
   const cc::LayerTreeHostImpl& GetImplDeprecated() const override {
     return host_impl_;
   }
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate) override {}
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const cc::BrowserControlsOffsetTagsInfo>
+          offset_tags_info) override {}
   bool HasScrollLinkedAnimation(cc::ElementId for_scroller) const override {
     return false;
   }
@@ -242,10 +247,12 @@ class MockInputHandler : public cc::InputHandler {
 
   void SetDeferBeginMainFrame(bool defer_begin_main_frame) const override {}
 
-  MOCK_METHOD3(UpdateBrowserControlsState,
+  MOCK_METHOD4(UpdateBrowserControlsState,
                void(cc::BrowserControlsState constraints,
                     cc::BrowserControlsState current,
-                    bool animate));
+                    bool animate,
+                    base::optional_ref<const cc::BrowserControlsOffsetTagsInfo>
+                        offset_tags_info));
 
  private:
   bool is_scrolling_root_ = true;
@@ -1783,13 +1790,15 @@ TEST_P(InputHandlerProxyTest, TouchMoveBlockingAddedAfterPassiveTouchStart) {
 
 TEST_P(InputHandlerProxyTest, UpdateBrowserControlsState) {
   VERIFY_AND_RESET_MOCKS();
-  EXPECT_CALL(mock_input_handler_,
-              UpdateBrowserControlsState(cc::BrowserControlsState::kShown,
-                                         cc::BrowserControlsState::kBoth, true))
+  EXPECT_CALL(
+      mock_input_handler_,
+      UpdateBrowserControlsState(cc::BrowserControlsState::kShown,
+                                 cc::BrowserControlsState::kBoth, true, _))
       .Times(1);
 
-  input_handler_->UpdateBrowserControlsState(
-      cc::BrowserControlsState::kShown, cc::BrowserControlsState::kBoth, true);
+  input_handler_->UpdateBrowserControlsState(cc::BrowserControlsState::kShown,
+                                             cc::BrowserControlsState::kBoth,
+                                             true, std::nullopt);
   VERIFY_AND_RESET_MOCKS();
 }
 

third_party/blink/renderer/platform/widget/input/widget_input_handler_impl.cc

@@ -220,9 +220,10 @@ void WidgetInputHandlerImpl::GetFrameWidgetInputHandler(
 void WidgetInputHandlerImpl::UpdateBrowserControlsState(
     cc::BrowserControlsState constraints,
     cc::BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info) {
   input_handler_manager_->UpdateBrowserControlsState(constraints, current,
-                                                     animate);
+                                                     animate, offset_tags_info);
 }
 
 void WidgetInputHandlerImpl::RunOnMainThread(base::OnceClosure closure) {

third_party/blink/renderer/platform/widget/input/widget_input_handler_impl.h

@@ -8,6 +8,7 @@
 #include "base/memory/weak_ptr.h"
 #include "base/task/single_thread_task_runner.h"
 #include "build/build_config.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/input/browser_controls_state.h"
 #include "mojo/public/cpp/bindings/associated_receiver.h"
 #include "mojo/public/cpp/bindings/direct_receiver.h"
@@ -79,9 +80,12 @@ class WidgetInputHandlerImpl : public mojom::blink::WidgetInputHandler {
   void GetFrameWidgetInputHandler(
       mojo::PendingAssociatedReceiver<mojom::blink::FrameWidgetInputHandler>
           interface_request) override;
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate) override;
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      const std::optional<cc::BrowserControlsOffsetTagsInfo>& offset_tags_info)
+      override;
 
   void InputWasProcessed();
 

third_party/blink/renderer/platform/widget/input/widget_input_handler_manager.cc

@@ -15,8 +15,10 @@
 #include "base/notreached.h"
 #include "base/task/single_thread_task_runner.h"
 #include "base/time/time.h"
+#include "base/types/optional_ref.h"
 #include "build/build_config.h"
 #include "cc/base/features.h"
+#include "cc/input/browser_controls_offset_tags_info.h"
 #include "cc/metrics/event_metrics.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/paint_holding_reason.h"
@@ -1167,14 +1169,16 @@ void WidgetInputHandlerManager::ClearClient() {
 void WidgetInputHandlerManager::UpdateBrowserControlsState(
     cc::BrowserControlsState constraints,
     cc::BrowserControlsState current,
-    bool animate) {
+    bool animate,
+    base::optional_ref<const cc::BrowserControlsOffsetTagsInfo>
+        offset_tags_info) {
   if (!input_handler_proxy_) {
     return;
   }
 
   DCHECK(InputThreadTaskRunner()->BelongsToCurrentThread());
   input_handler_proxy_->UpdateBrowserControlsState(constraints, current,
-                                                   animate);
+                                                   animate, offset_tags_info);
 }
 
 void WidgetInputHandlerManager::FlushCompositorQueueForTesting() {

third_party/blink/renderer/platform/widget/input/widget_input_handler_manager.h

@@ -10,6 +10,7 @@
 #include <optional>
 
 #include "base/task/single_thread_task_runner.h"
+#include "base/types/optional_ref.h"
 #include "build/build_config.h"
 #include "cc/input/browser_controls_state.h"
 #include "cc/trees/paint_holding_reason.h"
@@ -172,9 +173,12 @@ class PLATFORM_EXPORT WidgetInputHandlerManager final
 
   void ClearClient();
 
-  void UpdateBrowserControlsState(cc::BrowserControlsState constraints,
-                                  cc::BrowserControlsState current,
-                                  bool animate);
+  void UpdateBrowserControlsState(
+      cc::BrowserControlsState constraints,
+      cc::BrowserControlsState current,
+      bool animate,
+      base::optional_ref<const cc::BrowserControlsOffsetTagsInfo>
+          offset_tags_info);
 
   MainThreadEventQueue* input_event_queue() { return input_event_queue_.get(); }
 

third_party/blink/tools/blinkpy/presubmit/audit_non_blink_usage.py

@@ -529,6 +529,7 @@ _CONFIG = [
             'cc::kPixelsPerLineStep',
             'cc::kMinFractionToStepWhenPaging',
             'cc::kPercentDeltaForDirectionalScroll',
+            'cc::BrowserControlsOffsetTagsInfo',
             'cc::MainThreadScrollingReason',
             'cc::ManipulationInfo',
             'cc::ScrollSnapAlign',