Add IPC allowing GPU process to tell browser process to temporarily drop a front buffer.

content/browser/gpu/gpu_process_host_ui_shim.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_BROWSER_GPU_GPU_PROCESS_HOST_UI_SHIM_H_
 #define CONTENT_BROWSER_GPU_GPU_PROCESS_HOST_UI_SHIM_H_
 #pragma once
 
 // This class lives on the UI thread and supports classes like the
 // BackingStoreProxy, which must live on the UI thread. The IO thread
@@ skipping 76 matching lines @@
                     int32 route_id,
                     gfx::Size size);
 #endif
 
   void OnGraphicsInfoCollected(const content::GPUInfo& gpu_info);
 
   void OnAcceleratedSurfaceBuffersSwapped(
       const GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params& params);
   void OnAcceleratedSurfacePostSubBuffer(
       const GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params& params);
+  void OnAcceleratedSurfaceSuspend(int32 surface_id);
 
 #if defined(OS_MACOSX) || defined(UI_COMPOSITOR_IMAGE_TRANSPORT)
   void OnAcceleratedSurfaceNew(
       const GpuHostMsg_AcceleratedSurfaceNew_Params& params);
 #endif
 
 #if defined(UI_COMPOSITOR_IMAGE_TRANSPORT)
   void OnAcceleratedSurfaceRelease(
       const GpuHostMsg_AcceleratedSurfaceRelease_Params& params);
 #endif
 
   // The serial number of the GpuProcessHost / GpuProcessHostUIShim pair.
   int host_id_;
 };
 
 #endif  // CONTENT_BROWSER_GPU_GPU_PROCESS_HOST_UI_SHIM_H_