Delete background tab IOSurfaces on Mac.

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>
 #include <list>
@@ skipping 267 matching lines @@
       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 bool HasAcceleratedSurface(const gfx::Size& desired_size) OVERRIDE;
+  virtual void AboutToWaitForUpdateMsg() OVERRIDE;
   virtual void GetScreenInfo(WebKit::WebScreenInfo* results) OVERRIDE;
   virtual gfx::Rect GetRootWindowBounds() OVERRIDE;
   virtual gfx::GLSurfaceHandle GetCompositingSurface() OVERRIDE;
 
   void DrawAcceleratedSurfaceInstance(
       CGLContextObj context,
       gfx::PluginWindowHandle plugin_handle,
       NSSize size);
   // Forces the textures associated with any accelerated plugin instances
   // to be reloaded.
@@ skipping 115 matching lines @@
 
   // The text to be shown in the tooltip, supplied by the renderer.
   string16 tooltip_text_;
 
   // Factory used to safely scope delayed calls to ShutdownHost().
   base::WeakPtrFactory<RenderWidgetHostViewMac> weak_factory_;
 
   // selected text on the renderer.
   std::string selected_text_;
 
-  gfx::PluginWindowHandle compositing_surface_;
-
   // List of pending swaps for deferred acking:
   //   pairs of (route_id, gpu_host_id).
   std::list<std::pair<int32, int32> > pending_swap_buffers_acks_;
 
   // The fullscreen window used for pepper flash.
   scoped_nsobject<NSWindow> pepper_fullscreen_window_;
   scoped_nsobject<FullscreenWindowManager> fullscreen_window_manager_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewMac);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_