Avoid exposing cc::Layer tree to CompositorProxy

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

Index: third_party/WebKit/Source/platform/graphics/CompositorMutableStateProvider.h
diff --git a/third_party/WebKit/Source/platform/graphics/CompositorMutableStateProvider.h b/third_party/WebKit/Source/platform/graphics/CompositorMutableStateProvider.h
index 7cd920bf8191bfd3b9ca8bc96251de4e3d039ac9..225af89ee409db6e41e235a7c786b474c0a7507a 100644
--- a/third_party/WebKit/Source/platform/graphics/CompositorMutableStateProvider.h
+++ b/third_party/WebKit/Source/platform/graphics/CompositorMutableStateProvider.h
@@ -5,13 +5,10 @@
 #ifndef CompositorMutableStateProvider_h
 #define CompositorMutableStateProvider_h
 
-#include "platform/PlatformExport.h"
 #include <cstdint>
 #include <memory>
-
-namespace cc {
-class LayerTreeImpl;
-}  // namespace cc
+#include "platform/PlatformExport.h"
+#include "platform/graphics/CompositorMutableProperties.h"
 
 namespace blink {
 
@@ -22,14 +19,14 @@ struct CompositorMutations;
 // around per-element bits of this state.
 class PLATFORM_EXPORT CompositorMutableStateProvider {
  public:
-  CompositorMutableStateProvider(cc::LayerTreeImpl*, CompositorMutations*);
+  CompositorMutableStateProvider(ProxyCompositorMutablePropertiesMap*,
+                                 CompositorMutations*);
   ~CompositorMutableStateProvider();
 
-  std::unique_ptr<CompositorMutableState> GetMutableStateFor(
-      uint64_t element_id);
+  std::unique_ptr<CompositorMutableState> GetMutableStateFor(uint64_t proxy_id);
 
  private:
-  cc::LayerTreeImpl* tree_;
+  ProxyCompositorMutablePropertiesMap* input_properties_;
   CompositorMutations* mutations_;
 };