[TreesInViz] Pass client BeginFrameArgs with LayerTreeUpdates.

Some cc_unittests expect to be able to draw without a valid BeginFrame,
by using faked BeginFrameArgs for testing. We need to send these
BeginFrameArgs to the LayerContextImpl too, otherwise there can be a race
where LayerContextImpl tries to draw without ever having received valid
BeginFrameArgs.

This fixes running the *RunSingleThread_DelegatingRenderer tests.

Bug: 389147356
Change-Id: I9901c654f1853524797c53fef4110e3cf341eec0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6344045
Auto-Submit: Victor Miura <vmiura@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Commit-Queue: Alex Gough <ajgo@chromium.org>
Reviewed-by: Alex Gough <ajgo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1431700}

cc/mojo_embedder/viz_layer_context.cc

@@ -745,6 +745,7 @@ void VizLayerContext::UpdateDisplayTreeFrom(
     viz::RasterContextProvider& context_provider) {
   auto& property_trees = *tree.property_trees();
   auto update = viz::mojom::LayerTreeUpdate::New();
+  update->begin_frame_args = tree.CurrentBeginFrameArgs();
   update->source_frame_number = tree.source_frame_number();
   update->trace_id = tree.trace_id().value();
   update->device_viewport = tree.GetDeviceViewport();

components/viz/service/layers/layer_context_impl.cc

@@ -875,10 +875,8 @@ LayerContextImpl::~LayerContextImpl() {
 }
 
 void LayerContextImpl::BeginFrame(const BeginFrameArgs& args) {
-  // TODO(rockot): Manage these flags properly.
-  last_begin_frame_args_ = args;
-
   if (base::FeatureList::IsEnabled(features::kTreeAnimationsInViz)) {
+    // TODO(vmiura): Manage these flags properly.
     const bool has_damage = true;
     compositor_sink_->SetLayerContextWantsBeginFrames(false);
     if (!host_impl_->CanDraw()) {
@@ -1226,16 +1224,17 @@ base::expected<void, std::string> LayerContextImpl::DoUpdateDisplayTree(
     compositor_sink_->SetLayerContextWantsBeginFrames(true);
   } else {
     if (host_impl_->CanDraw()) {
-      host_impl_->WillBeginImplFrame(last_begin_frame_args_);
+      host_impl_->WillBeginImplFrame(update->begin_frame_args);
 
       cc::LayerTreeHostImpl::FrameData frame;
       const bool has_damage = true;
-      frame.begin_frame_ack = BeginFrameAck(last_begin_frame_args_, has_damage);
-      frame.origin_begin_main_frame_args = last_begin_frame_args_;
+      frame.begin_frame_ack =
+          BeginFrameAck(update->begin_frame_args, has_damage);
+      frame.origin_begin_main_frame_args = update->begin_frame_args;
       host_impl_->PrepareToDraw(&frame);
       host_impl_->DrawLayers(&frame);
       host_impl_->DidDrawAllLayers(frame);
-      host_impl_->DidFinishImplFrame(last_begin_frame_args_);
+      host_impl_->DidFinishImplFrame(update->begin_frame_args);
     }
   }
   return base::ok();

components/viz/service/layers/layer_context_impl.h

@@ -134,8 +134,6 @@ class LayerContextImpl : public cc::LayerTreeHostImplClient,
   const std::unique_ptr<cc::RenderingStatsInstrumentation> rendering_stats_;
   const std::unique_ptr<cc::LayerTreeHostImpl> host_impl_;
 
-  BeginFrameArgs last_begin_frame_args_;
-
   std::vector<TransferableResource> next_frame_resources_;
 
   raw_ptr<cc::LayerTreeFrameSinkClient> frame_sink_client_ = nullptr;

services/viz/public/mojom/compositing/layer_context.mojom

@@ -29,6 +29,8 @@ import "ui/gfx/geometry/mojom/geometry.mojom";
 // TODO(https://crbug.com/40902503): Split less frequently updated fields out
 // into an optional substructure to reduce serialization load.
 struct LayerTreeUpdate {
+  BeginFrameArgs begin_frame_args;
+
   // The main frame commit whose tree is driving this update. Incremented over
   // time with each client-side commit.
   int32 source_frame_number;

testing/buildbot/filters/trees_in_viz.cc_unittests.filter

@@ -15,6 +15,7 @@
 -LayerTreeHostImplViewportCoveredTest.ViewportCoveredScaled
 -LayerTreeHostImplTestDrawAndTestDamage.FrameIncludesDamageRect/CommitToActiveTree
 -LayerTreeHostImplTestDrawAndTestDamage.FrameIncludesDamageRect/CommitToPendingTree
+-LayerTreeHostPictureTestForceRecalculateScales.RunSingleThread_DelegatingRenderer
 -LayerTreeTestMaskLayerForSurfaceWithContentRectNotAtOriginWithLayerList.RunSingleThread_DelegatingRenderer
 
 # These tests rely LayerTreeHostImpl to set certain flags in CompositorFrames
@@ -61,15 +62,3 @@
 # TODO(crbug.com/401568010) Investigate LayerTreeHostImplTest.LayersFreeTextures
 -LayerTreeHostImplTest.LayersFreeTextures/CommitToActiveTree
 -LayerTreeHostImplTest.LayersFreeTextures/CommitToPendingTree
-
-# TODO(crbug.com/389147356): Implement single-threaded mode, which all of these
-# tests operate in.
--LayerTreeHostPictureTestForceRecalculateScales.RunSingleThread_DelegatingRenderer
--LayerTreeHostScrollTestImplScrollUnderMainThreadScrollingParent.RunSingleThread_DelegatingRenderer
--LayerTreeHostScrollTestPropertyTreeUpdate.RunSingleThread_DelegatingRenderer
--LayerTreeHostScrollTestScrollNonDrawnLayer.RunSingleThread_DelegatingRenderer
--LayerTreeHostScrollTestScrollZeroMaxScrollOffset.RunSingleThread_DelegatingRenderer
--LayerTreeHostTestHudLayerWithLayerLists.RunSingleThread_DelegatingRenderer
--LayerTreeHostTestLayerListSurfaceDamage.RunSingleThread_DelegatingRenderer
--LayerTreeTestPageScaleFlags.RunSingleThread_DelegatingRenderer
--NonScrollingMainThreadScrollHitTestRegion.RunSingleThread_DelegatingRenderer