cc: Make separate interface for BeginFrame ipc from OutputSurface

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index ddb315f389390afd713f2387facbcf27e083e4c9..e297bc7158aa604ea6d70e0eca368c6a95fb3daa 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -268,8 +268,7 @@ LayerTreeHostImpl::LayerTreeHostImpl(
     SharedBitmapManager* shared_bitmap_manager,
     GpuMemoryBufferManager* gpu_memory_buffer_manager,
     int id)
-    : BeginFrameSourceMixIn(),
-      client_(client),
+    : client_(client),
       proxy_(proxy),
       use_gpu_rasterization_(false),
       input_handler_client_(NULL),
@@ -1440,10 +1439,6 @@ void LayerTreeHostImpl::SetNeedsRedrawRect(const gfx::Rect& damage_rect) {
   client_->SetNeedsRedrawRectOnImplThread(damage_rect);
 }
 
-void LayerTreeHostImpl::BeginFrame(const BeginFrameArgs& args) {
-  CallOnBeginFrame(args);
-}
-
 void LayerTreeHostImpl::DidSwapBuffers() {
   client_->DidSwapBuffersOnImplThread();
 }
@@ -1681,13 +1676,6 @@ bool LayerTreeHostImpl::SwapBuffers(const LayerTreeHostImpl::FrameData& frame) {
   return true;
 }
 
-void LayerTreeHostImpl::OnNeedsBeginFramesChange(bool enable) {
-  if (output_surface_)
-    output_surface_->SetNeedsBeginFrame(enable);
-  else
-    DCHECK(!enable);
-}
-
 void LayerTreeHostImpl::WillBeginImplFrame(const BeginFrameArgs& args) {
   // Sample the frame time now. This time will be used for updating animations
   // when we draw.
@@ -3240,10 +3228,6 @@ BeginFrameArgs LayerTreeHostImpl::CurrentBeginFrameArgs() const {
                                 BeginFrameArgs::DefaultInterval());
 }
 
-void LayerTreeHostImpl::AsValueInto(base::debug::TracedValue* value) const {
-  return AsValueWithFrameInto(NULL, value);
-}
-
 scoped_refptr<base::debug::ConvertableToTraceFormat>
 LayerTreeHostImpl::AsValue() const {
   return AsValueWithFrame(NULL);
@@ -3257,6 +3241,10 @@ LayerTreeHostImpl::AsValueWithFrame(FrameData* frame) const {
   return state;
 }
 
+void LayerTreeHostImpl::AsValueInto(base::debug::TracedValue* value) const {
+  return AsValueWithFrameInto(NULL, value);
+}
+
 void LayerTreeHostImpl::AsValueWithFrameInto(
     FrameData* frame,
     base::debug::TracedValue* state) const {