Delete shared state transfer buffer upon command-buffer deletion.

content/common/gpu/client/command_buffer_proxy_impl.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_COMMON_GPU_CLIENT_COMMAND_BUFFER_PROXY_IMPL_H_
 #define CONTENT_COMMON_GPU_CLIENT_COMMAND_BUFFER_PROXY_IMPL_H_
 
 #if defined(ENABLE_GPU)
 
 #include <map>
@@ skipping 145 matching lines @@
 
   base::Callback<void(const GpuMemoryAllocationForRenderer&)>
       memory_allocation_changed_callback_;
 
   GpuConsoleMessageCallback console_message_callback_;
 
   // Tasks to be invoked in SignalSyncPoint responses.
   uint32 next_signal_id_;
   SignalTaskMap signal_tasks_;
 
+  // ID of transfer buffer containing shared state.
+  int32 state_buffer_;
+
   DISALLOW_COPY_AND_ASSIGN(CommandBufferProxyImpl);
 };
 
 #endif  // ENABLE_GPU
 
 #endif  // CONTENT_COMMON_GPU_CLIENT_COMMAND_BUFFER_PROXY_IMPL_H_