Let every "accelerated IO surface swapped" message have an identifier of the surface.

chrome/common/gpu_messages_internal.h

 // Copyright (c) 2010 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.
 
 // This header is meant to be included in multiple passes, hence no traditional
 // header guard. It is included by backing_store_messages_internal.h
 // See ipc_message_macros.h for explanation of the macros and passes.
 
 // This file needs to be included again, even though we're actually included
 // from it via utility_messages.h.
@@ skipping 124 matching lines @@
   // supported), is sent from the GPU process to the browser to indicate that a
   // new backing store was allocated for the given "window" (fake
   // PluginWindowHandle). The renderer ID and render view ID are needed in
   // order to uniquely identify the RenderWidgetHostView on the browser side.
   IPC_MESSAGE_CONTROL1(GpuHostMsg_AcceleratedSurfaceSetIOSurface,
                        GpuHostMsg_AcceleratedSurfaceSetIOSurface_Params)
 
   // This message notifies the browser process that the renderer
   // swapped the buffers associated with the given "window", which
   // should cause the browser to redraw the compositor's contents.
-  IPC_MESSAGE_CONTROL3(GpuHostMsg_AcceleratedSurfaceBuffersSwapped,
+  IPC_MESSAGE_CONTROL4(GpuHostMsg_AcceleratedSurfaceBuffersSwapped,
                        int32, /* renderer_id */
                        int32, /* render_view_id */
-                       gfx::PluginWindowHandle /* window */)
+                       gfx::PluginWindowHandle /* window */,
+                       uint64 /* surface_id */)
 #endif
 
 IPC_END_MESSAGES(GpuHost)
 
 //------------------------------------------------------------------------------
 // GPU Channel Messages
 // These are messages from a renderer process to the GPU process.
 IPC_BEGIN_MESSAGES(GpuChannel)
 
   // Tells the GPU process to create a new command buffer that renders directly
@@ skipping 208 matching lines @@
 
   // GpuVideoDecoder report output format change.
   IPC_MESSAGE_ROUTED1(GpuVideoDecoderHostMsg_MediaFormatChange,
                       GpuVideoDecoderFormatChangeParam)
 
   // GpuVideoDecoder report error.
   IPC_MESSAGE_ROUTED1(GpuVideoDecoderHostMsg_ErrorNotification,
                       GpuVideoDecoderErrorInfoParam)
 
 IPC_END_MESSAGES(GpuVideoDecoderHost)