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

content/browser/renderer_host/render_widget_host_view_mac.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_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 #pragma once
 
 #import <Cocoa/Cocoa.h>
 
@@ skipping 246 matching lines @@
       gfx::PluginWindowHandle window,
       int32 width,
       int32 height,
       TransportDIB::Handle transport_dib) OVERRIDE;
   virtual void AcceleratedSurfaceBuffersSwapped(
       const GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params& params,
       int gpu_host_id) OVERRIDE;
   virtual void AcceleratedSurfacePostSubBuffer(
       const GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params& params,
       int gpu_host_id) OVERRIDE;
+  virtual void AcceleratedSurfaceSuspend() OVERRIDE;
   virtual void GetScreenInfo(WebKit::WebScreenInfo* results) OVERRIDE;
   virtual gfx::Rect GetRootWindowBounds() OVERRIDE;
   virtual gfx::PluginWindowHandle GetCompositingSurface() OVERRIDE;
 
   // Returns |true| if a context menu is currently being shown.
   bool is_showing_context_menu() const { return is_showing_context_menu_; }
 
   void DrawAcceleratedSurfaceInstance(
       CGLContextObj context,
       gfx::PluginWindowHandle plugin_handle,
@@ skipping 120 matching lines @@
   // hidden until the software backing store has been updated. This variable is
   // set when the gpu widget needs to be hidden once a paint is completed.
   bool needs_gpu_visibility_update_after_repaint_;
 
   gfx::PluginWindowHandle compositing_surface_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewMac);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_