cc: Make separate interface for BeginFrame ipc from OutputSurface

cc/trees/layer_tree_host_impl.h

Index: cc/trees/layer_tree_host_impl.h
diff --git a/cc/trees/layer_tree_host_impl.h b/cc/trees/layer_tree_host_impl.h
index 51ef8b01a0315871045a73ca6ae9ec68ff2267bd..11eabdb32156a2cec00e67713ad592e1612a763d 100644
--- a/cc/trees/layer_tree_host_impl.h
+++ b/cc/trees/layer_tree_host_impl.h
@@ -31,7 +31,6 @@
 #include "cc/quads/render_pass.h"
 #include "cc/resources/resource_provider.h"
 #include "cc/resources/tile_manager.h"
-#include "cc/scheduler/begin_frame_source.h"
 #include "cc/scheduler/draw_result.h"
 #include "skia/ext/refptr.h"
 #include "third_party/skia/include/core/SkColor.h"
@@ -112,7 +111,6 @@ class CC_EXPORT LayerTreeHostImpl
       public OutputSurfaceClient,
       public TopControlsManagerClient,
       public ScrollbarAnimationControllerClient,
-      public BeginFrameSourceMixIn,
       public base::SupportsWeakPtr<LayerTreeHostImpl> {
  public:
   static scoped_ptr<LayerTreeHostImpl> Create(
@@ -125,9 +123,6 @@ class CC_EXPORT LayerTreeHostImpl
       int id);
   virtual ~LayerTreeHostImpl();
 
-  // BeginFrameSourceMixIn implementation
-  virtual void OnNeedsBeginFramesChange(bool needs_begin_frames) override;
-
   // InputHandler implementation
   virtual void BindToClient(InputHandlerClient* client) override;
   virtual InputHandler::ScrollStatus ScrollBegin(
@@ -255,7 +250,6 @@ class CC_EXPORT LayerTreeHostImpl
   virtual void CommitVSyncParameters(base::TimeTicks timebase,
                                      base::TimeDelta interval) override;
   virtual void SetNeedsRedrawRect(const gfx::Rect& rect) override;
-  virtual void BeginFrame(const BeginFrameArgs& args) override;
 
   virtual void SetExternalDrawConstraints(
       const gfx::Transform& transform,
@@ -429,7 +423,7 @@ class CC_EXPORT LayerTreeHostImpl
     return begin_impl_frame_interval_;
   }
 
-  virtual void AsValueInto(base::debug::TracedValue* value) const override;
+  void AsValueInto(base::debug::TracedValue* value) const;
   void AsValueWithFrameInto(FrameData* frame,
                             base::debug::TracedValue* value) const;
   scoped_refptr<base::debug::ConvertableToTraceFormat> AsValue() const;