Add CCDelegatingRenderer, and corresponding IPCs

content/renderer/gpu/compositor_output_surface.h

Index: content/renderer/gpu/compositor_output_surface.h
diff --git a/content/renderer/gpu/compositor_output_surface.h b/content/renderer/gpu/compositor_output_surface.h
index edff94064aee127323f93fcb50577908adf6852e..85380a9f29ef252470585500233debb50ddbbd60 100644
--- a/content/renderer/gpu/compositor_output_surface.h
+++ b/content/renderer/gpu/compositor_output_surface.h
@@ -14,6 +14,10 @@
 #include "third_party/WebKit/Source/Platform/chromium/public/WebCompositorOutputSurface.h"
 #include "third_party/WebKit/Source/Platform/chromium/public/WebCompositorSoftwareOutputDevice.h"
 
+namespace WebKit {
+  struct WebCompositorFrameAck;
+}
+
 namespace base {
   class TaskRunner;
 }
@@ -71,6 +75,8 @@ class CompositorOutputSurface
   void OnMessageReceived(const IPC::Message& message);
   void OnUpdateVSyncParameters(
       base::TimeTicks timebase, base::TimeDelta interval);
+  void OnSwapCompositorFrameACK(const WebKit::WebCompositorFrameAck& ack);
+  bool Send(IPC::Message* message);
 
   scoped_refptr<IPC::ForwardingMessageFilter> output_surface_filter_;
   WebKit::WebCompositorOutputSurfaceClient* client_;