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

gpu/command_buffer/service/gpu_processor.h

 // Copyright (c) 2009 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 GPU_COMMAND_BUFFER_SERVICE_GPU_PROCESSOR_H_
 #define GPU_COMMAND_BUFFER_SERVICE_GPU_PROCESSOR_H_
 
 #include <vector>
 
 #include "app/surface/transport_dib.h"
@@ skipping 65 matching lines @@
   // manually. Returns an opaque identifier for the new backing store.
   // There are two versions of this method: one for use with the IOSurface
   // available in Mac OS X 10.6; and, one for use with the
   // TransportDIB-based version used on Mac OS X 10.5.
   virtual uint64 SetWindowSizeForIOSurface(const gfx::Size& size);
   virtual TransportDIB::Handle SetWindowSizeForTransportDIB(
       const gfx::Size& size);
   virtual void SetTransportDIBAllocAndFree(
       Callback2<size_t, TransportDIB::Handle*>::Type* allocator,
       Callback1<TransportDIB::Id>::Type* deallocator);
+  // Returns the id of the current IOSurface, or 0.
+  virtual uint64 GetSurfaceId();
 #endif
 
   // Sets a callback which is called when a SwapBuffers command is processed.
   // Must be called after Initialize().
   // It is not defined on which thread this callback is called.
   virtual void SetSwapBuffersCallback(Callback0::Type* callback);
 
   // Get the GLES2Decoder associated with this processor.
   gles2::GLES2Decoder* decoder() const { return decoder_.get(); }
 
@@ skipping 26 matching lines @@
   scoped_ptr<AcceleratedSurface> surface_;
 #endif
 
   ScopedRunnableMethodFactory<GPUProcessor> method_factory_;
   scoped_ptr<Callback0::Type> wrapped_swap_buffers_callback_;
 };
 
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_GPU_PROCESSOR_H_