Revert "Wire up Opacity on Fuchsia, round 2 (#14024)" (#14543)

This reverts commit d117ac9.

Author: iskakaushik

ci/licenses_golden/licenses_flutter

@@ -48,10 +48,6 @@ FILE: ../../../flutter/flow/layers/color_filter_layer_unittests.cc
 FILE: ../../../flutter/flow/layers/container_layer.cc
 FILE: ../../../flutter/flow/layers/container_layer.h
 FILE: ../../../flutter/flow/layers/container_layer_unittests.cc
-FILE: ../../../flutter/flow/layers/elevated_container_layer.cc
-FILE: ../../../flutter/flow/layers/elevated_container_layer.h
-FILE: ../../../flutter/flow/layers/fuchsia_system_composited_layer.cc
-FILE: ../../../flutter/flow/layers/fuchsia_system_composited_layer.h
 FILE: ../../../flutter/flow/layers/layer.cc
 FILE: ../../../flutter/flow/layers/layer.h
 FILE: ../../../flutter/flow/layers/layer_tree.cc

flow/BUILD.gn

@@ -28,8 +28,6 @@ source_set("flow") {
     "layers/color_filter_layer.h",
     "layers/container_layer.cc",
     "layers/container_layer.h",
-    "layers/elevated_container_layer.cc",
-    "layers/elevated_container_layer.h",
     "layers/layer.cc",
     "layers/layer.h",
     "layers/layer_tree.cc",
@@ -78,8 +76,6 @@ source_set("flow") {
     sources += [
       "layers/child_scene_layer.cc",
       "layers/child_scene_layer.h",
-      "layers/fuchsia_system_composited_layer.cc",
-      "layers/fuchsia_system_composited_layer.h",
       "scene_update_context.cc",
       "scene_update_context.h",
       "view_holder.cc",

flow/layers/child_scene_layer.cc

@@ -20,25 +20,10 @@ ChildSceneLayer::ChildSceneLayer(zx_koid_t layer_id,
 void ChildSceneLayer::Preroll(PrerollContext* context, const SkMatrix& matrix) {
   TRACE_EVENT0("flutter", "ChildSceneLayer::Preroll");
   set_needs_system_composite(true);
-
-  // An alpha "hole punch" is required if the frame behind us is not opaque.
-  if (!context->is_opaque) {
-    set_paint_bounds(
-        SkRect::MakeXYWH(offset_.fX, offset_.fY, size_.fWidth, size_.fHeight));
-  }
 }
 
 void ChildSceneLayer::Paint(PaintContext& context) const {
-  TRACE_EVENT0("flutter", "ChildSceneLayer::Paint");
-  FML_DCHECK(needs_painting());
-
-  // If we are being rendered into our own frame using the system compositor,
-  // then it is neccesary to "punch a hole" in the canvas/frame behind us so
-  // that group opacity looks correct.
-  SkPaint paint;
-  paint.setColor(SK_ColorTRANSPARENT);
-  paint.setBlendMode(SkBlendMode::kSrc);
-  context.leaf_nodes_canvas->drawRect(paint_bounds(), paint);
+  FML_NOTREACHED() << "This layer never needs painting.";
 }
 
 void ChildSceneLayer::UpdateScene(SceneUpdateContext& context) {

flow/layers/container_layer.cc

@@ -9,7 +9,8 @@ namespace flutter {
 ContainerLayer::ContainerLayer() {}
 
 void ContainerLayer::Add(std::shared_ptr<Layer> layer) {
-  layers_.emplace_back(std::move(layer));
+  layer->set_parent(this);
+  layers_.push_back(std::move(layer));
 }
 
 void ContainerLayer::Preroll(PrerollContext* context, const SkMatrix& matrix) {

flow/layers/container_layer.h

@@ -14,7 +14,7 @@ class ContainerLayer : public Layer {
  public:
   ContainerLayer();
 
-  virtual void Add(std::shared_ptr<Layer> layer);
+  void Add(std::shared_ptr<Layer> layer);
 
   void Preroll(PrerollContext* context, const SkMatrix& matrix) override;
   void Paint(PaintContext& context) const override;

flow/layers/elevated_container_layer.cc

@@ -10,9 +10,10 @@
 namespace flutter {
 
 Layer::Layer()
-    : paint_bounds_(SkRect::MakeEmpty()),
-      unique_id_(NextUniqueID()),
-      needs_system_composite_(false) {}
+    : parent_(nullptr),
+      needs_system_composite_(false),
+      paint_bounds_(SkRect::MakeEmpty()),
+      unique_id_(NextUniqueID()) {}
 
 Layer::~Layer() = default;
 

flow/layers/elevated_container_layer.h

@@ -42,6 +42,8 @@ static constexpr SkRect kGiantRect = SkRect::MakeLTRB(-1E9F, -1E9F, 1E9F, 1E9F);
 // This should be an exact copy of the Clip enum in painting.dart.
 enum Clip { none, hardEdge, antiAlias, antiAliasWithSaveLayer };
 
+class ContainerLayer;
+
 struct PrerollContext {
   RasterCache* raster_cache;
   GrContext* gr_context;
@@ -51,21 +53,13 @@ struct PrerollContext {
   SkRect cull_rect;
   bool surface_needs_readback;
 
-  // These allow us to paint in the end of subtree Preroll.
+  // The following allows us to paint in the end of subtree preroll
   const Stopwatch& raster_time;
   const Stopwatch& ui_time;
   TextureRegistry& texture_registry;
   const bool checkerboard_offscreen_layers;
-
-  // These allow us to make use of the scene metrics during Preroll.
-  float frame_physical_depth;
-  float frame_device_pixel_ratio;
-
-  // These allow us to track properties like elevation, opacity, and the
-  // prescence of a platform view during Preroll.
   float total_elevation = 0.0f;
   bool has_platform_view = false;
-  bool is_opaque = true;
 };
 
 // Represents a single composited layer. Created on the UI thread but then
@@ -123,10 +117,6 @@ class Layer {
     TextureRegistry& texture_registry;
     const RasterCache* raster_cache;
     const bool checkerboard_offscreen_layers;
-
-    // These allow us to make use of the scene metrics during Paint.
-    float frame_physical_depth;
-    float frame_device_pixel_ratio;
   };
 
   // Calls SkCanvas::saveLayer and restores the layer upon destruction. Also
@@ -163,6 +153,10 @@ class Layer {
   virtual void UpdateScene(SceneUpdateContext& context);
 #endif
 
+  ContainerLayer* parent() const { return parent_; }
+
+  void set_parent(ContainerLayer* parent) { parent_ = parent; }
+
   bool needs_system_composite() const { return needs_system_composite_; }
   void set_needs_system_composite(bool value) {
     needs_system_composite_ = value;
@@ -181,9 +175,10 @@ class Layer {
   uint64_t unique_id() const { return unique_id_; }
 
  private:
+  ContainerLayer* parent_;
+  bool needs_system_composite_;
   SkRect paint_bounds_;
   uint64_t unique_id_;
-  bool needs_system_composite_;
 
   static uint64_t NextUniqueID();