[TreesInViz] Add wire support for solid color scrollbar layers

This change wires the SolidColorScrollbarLayerImpl type to the
Viz LayerContextImpl.

Bug: 388877791
Change-Id: I938f624f02414c86442c61f7c78c014710e19e77
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6542132
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Jonathan Ross <jonross@chromium.org>
Commit-Queue: Victor Miura <vmiura@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1460099}

cc/layers/solid_color_scrollbar_layer_impl.h

@@ -37,6 +37,10 @@ class CC_EXPORT SolidColorScrollbarLayerImpl : public ScrollbarLayerImplBase {
 
   void set_color(SkColor4f color) { color_ = color; }
 
+  int thumb_thickness() const { return thumb_thickness_; }
+  int track_start() const { return track_start_; }
+  SkColor4f color() const { return color_; }
+
  protected:
   SolidColorScrollbarLayerImpl(LayerTreeImpl* tree_impl,
                                int id,

cc/mojo_embedder/viz_layer_context.cc

@@ -27,6 +27,7 @@
 #include "cc/layers/nine_patch_thumb_scrollbar_layer_impl.h"
 #include "cc/layers/painted_scrollbar_layer_impl.h"
 #include "cc/layers/picture_layer_impl.h"
+#include "cc/layers/solid_color_scrollbar_layer_impl.h"
 #include "cc/layers/surface_layer_impl.h"
 #include "cc/layers/texture_layer_impl.h"
 #include "cc/tiles/picture_layer_tiling.h"
@@ -626,6 +627,16 @@ void SerializePaintedScrollbarLayerExtra(
   extra->track_and_buttons_aperture = layer.track_and_buttons_aperture();
 }
 
+void SerializeSolidColorScrollbarLayerExtra(
+    SolidColorScrollbarLayerImpl& layer,
+    viz::mojom::SolidColorScrollbarLayerExtraPtr& extra) {
+  SerializeScrollbarLayerBaseExtra(static_cast<ScrollbarLayerImplBase&>(layer),
+                                   extra->scrollbar_base_extra);
+  extra->thumb_thickness = layer.thumb_thickness();
+  extra->track_start = layer.track_start();
+  extra->color = layer.color();
+}
+
 void SerializeSurfaceLayerExtra(SurfaceLayerImpl& layer,
                                 viz::mojom::SurfaceLayerExtraPtr& extra) {
   extra->surface_range = layer.range();
@@ -709,6 +720,17 @@ void SerializeLayer(LayerImpl& layer,
           std::move(painted_scrollbar_layer_extra));
       break;
     }
+    case mojom::LayerType::kSolidColorScrollbar: {
+      auto solid_color_scrollbar_layer_extra =
+          viz::mojom::SolidColorScrollbarLayerExtra::New();
+      SerializeSolidColorScrollbarLayerExtra(
+          static_cast<SolidColorScrollbarLayerImpl&>(layer),
+          solid_color_scrollbar_layer_extra);
+      wire.layer_extra =
+          viz::mojom::LayerExtra::NewSolidColorScrollbarLayerExtra(
+              std::move(solid_color_scrollbar_layer_extra));
+      break;
+    }
     case mojom::LayerType::kSurface: {
       auto surface_layer_extra = viz::mojom::SurfaceLayerExtra::New();
       SerializeSurfaceLayerExtra(static_cast<SurfaceLayerImpl&>(layer),

components/viz/service/layers/layer_context_impl.cc

@@ -26,6 +26,7 @@
 #include "cc/layers/nine_patch_thumb_scrollbar_layer_impl.h"
 #include "cc/layers/painted_scrollbar_layer_impl.h"
 #include "cc/layers/solid_color_layer_impl.h"
+#include "cc/layers/solid_color_scrollbar_layer_impl.h"
 #include "cc/layers/surface_layer_impl.h"
 #include "cc/layers/texture_layer_impl.h"
 #include "cc/layers/tile_display_layer_impl.h"
@@ -97,6 +98,17 @@ std::unique_ptr<cc::LayerImpl> CreateLayer(cc::LayerTreeHostImpl& host_impl,
     case cc::mojom::LayerType::kPicture:
       return std::make_unique<cc::TileDisplayLayerImpl>(tree, id);
 
+    case cc::mojom::LayerType::kSolidColorScrollbar: {
+      auto& extra = wire.layer_extra->get_solid_color_scrollbar_layer_extra();
+      cc::ScrollbarOrientation orientation =
+          extra->scrollbar_base_extra->is_horizontal_orientation
+              ? cc::ScrollbarOrientation::kHorizontal
+              : cc::ScrollbarOrientation::kVertical;
+      return cc::SolidColorScrollbarLayerImpl::Create(
+          &tree, id, orientation, extra->thumb_thickness, extra->track_start,
+          extra->scrollbar_base_extra->is_left_side_vertical_scrollbar);
+    }
+
     case cc::mojom::LayerType::kSurface:
       // The callback is triggered in the renderer side during WillDraw(),
       // and there is no need to do it in viz.
@@ -513,6 +525,14 @@ void UpdatePaintedScrollbarLayerExtra(
   layer.SetTrackAndButtonsAperture(extra->track_and_buttons_aperture);
 }
 
+void UpdateSolidColorScrollbarLayerExtra(
+    const mojom::SolidColorScrollbarLayerExtraPtr& extra,
+    cc::SolidColorScrollbarLayerImpl& layer) {
+  UpdateScrollbarLayerBaseExtra(
+      extra->scrollbar_base_extra,
+      static_cast<cc::ScrollbarLayerImplBase&>(layer));
+}
+
 void UpdateSurfaceLayerExtra(const mojom::SurfaceLayerExtraPtr& extra,
                              cc::SurfaceLayerImpl& layer) {
   layer.SetRange(extra->surface_range, extra->deadline_in_frames);
@@ -608,6 +628,11 @@ base::expected<void, std::string> UpdateLayer(const mojom::Layer& wire,
           wire.layer_extra->get_painted_scrollbar_layer_extra(),
           static_cast<cc::PaintedScrollbarLayerImpl&>(layer));
       break;
+    case cc::mojom::LayerType::kSolidColorScrollbar:
+      UpdateSolidColorScrollbarLayerExtra(
+          wire.layer_extra->get_solid_color_scrollbar_layer_extra(),
+          static_cast<cc::SolidColorScrollbarLayerImpl&>(layer));
+      break;
     case cc::mojom::LayerType::kSurface:
       UpdateSurfaceLayerExtra(wire.layer_extra->get_surface_layer_extra(),
                               static_cast<cc::SurfaceLayerImpl&>(layer));

services/viz/public/mojom/compositing/layer.mojom

@@ -124,6 +124,8 @@ struct NinePatchThumbScrollbarLayerExtra {
   cc.mojom.UIResourceId track_and_buttons_ui_resource_id;
 };
 
+// Extra fields in a cc::PaintedScrollbarLayerImpl that has been added
+// to a tree or modified in some interesting way since a prior tree update.
 struct PaintedScrollbarLayerExtra {
   ScrollbarLayerBaseExtra scrollbar_base_extra;
 
@@ -145,6 +147,16 @@ struct PaintedScrollbarLayerExtra {
   cc.mojom.UIResourceId thumb_ui_resource_id;
 };
 
+// Extra fields in a cc::SolidColorScrollbarLayerImpl that has been added
+// to a tree or modified in some interesting way since a prior tree update.
+struct SolidColorScrollbarLayerExtra {
+  ScrollbarLayerBaseExtra scrollbar_base_extra;
+
+  int32 thumb_thickness;
+  int32 track_start;
+  skia.mojom.SkColor4f color;
+};
+
 // Extra properties that are specific to a LayerImpl type.
 union LayerExtra {
   // Extra properties that are specific to MirrorLayerImpl.
@@ -153,6 +165,8 @@ union LayerExtra {
   NinePatchThumbScrollbarLayerExtra nine_patch_thumb_scrollbar_layer_extra;
   // Extra properties that are specific to PaintedScrollbarLayerImpl.
   PaintedScrollbarLayerExtra painted_scrollbar_layer_extra;
+  // Extra properties that are specific to SolidColorScrollbarLayerImpl.
+  SolidColorScrollbarLayerExtra solid_color_scrollbar_layer_extra;
   // Extra properties that are specific to SurfaceLayerImpl.
   SurfaceLayerExtra surface_layer_extra;
   // Extra properties that are specific to TextureLayerImpl.