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

This reverts commit d117ac9.

Author: Kaushik Iska

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;