Avoid exposing cc::Layer tree to CompositorProxy

third_party/WebKit/Source/platform/graphics/CompositorMutableState.h

Index: third_party/WebKit/Source/platform/graphics/CompositorMutableState.h
diff --git a/third_party/WebKit/Source/platform/graphics/CompositorMutableState.h b/third_party/WebKit/Source/platform/graphics/CompositorMutableState.h
index 4930a8144c474227743f1fa97be039c141f9e849..2084ccfd5dabda4681232b4e807f978877815283 100644
--- a/third_party/WebKit/Source/platform/graphics/CompositorMutableState.h
+++ b/third_party/WebKit/Source/platform/graphics/CompositorMutableState.h
@@ -9,20 +9,15 @@
 
 class SkMatrix44;
 
-namespace cc {
-class LayerImpl;
-}  // namespace cc
-
 namespace blink {
 
+class CompositorMutableProperties;
 class CompositorMutation;
 
 // This class wraps the compositor-owned, mutable state for a single element.
 class PLATFORM_EXPORT CompositorMutableState {
  public:
-  CompositorMutableState(CompositorMutation*,
-                         cc::LayerImpl* main,
-                         cc::LayerImpl* scroll);
+  CompositorMutableState(CompositorMutation*, CompositorMutableProperties*);
   ~CompositorMutableState();
 
   double Opacity() const;
@@ -39,8 +34,7 @@ class PLATFORM_EXPORT CompositorMutableState {
 
  private:
   CompositorMutation* mutation_;
-  cc::LayerImpl* main_layer_;
-  cc::LayerImpl* scroll_layer_;
+  CompositorMutableProperties* properties_;
 };
 
 }  // namespace blink