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

chrome/gpu/gpu_command_buffer_stub.cc

 // 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.
 
 #if defined(ENABLE_GPU)
 
 #include "base/process_util.h"
 #include "base/shared_memory.h"
 #include "build/build_config.h"
 #include "chrome/common/child_thread.h"
@@ skipping 180 matching lines @@
   } else {
     // TODO(kbr): figure out what to do here. It wouldn't be difficult
     // to support the compositor on 10.5, but the performance would be
     // questionable.
     NOTREACHED();
   }
 }
 
 void GpuCommandBufferStub::SwapBuffersCallback() {
   ChildThread* gpu_thread = ChildThread::current();
-  gpu_thread->Send(
-      new GpuHostMsg_AcceleratedSurfaceBuffersSwapped(renderer_id_,
-                                                      render_view_id_,
-                                                      handle_));
+  gpu_thread->Send(new GpuHostMsg_AcceleratedSurfaceBuffersSwapped(
+      renderer_id_, render_view_id_, handle_, processor_->GetSurfaceId()));
 }
 #endif  // defined(OS_MACOSX)
 
 #endif  // ENABLE_GPU