Added a unique command buffer ID for command buffers.

gpu/command_buffer/client/gpu_control.h

 // Copyright 2014 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_CLIENT_GPU_CONTROL_H_
 #define GPU_COMMAND_BUFFER_CLIENT_GPU_CONTROL_H_
 
 #include <stdint.h>
 
 #include <vector>
 
 #include "base/callback.h"
 #include "base/macros.h"
 #include "gpu/command_buffer/common/capabilities.h"
+#include "gpu/command_buffer/common/constants.h"
 #include "gpu/command_buffer/common/mailbox.h"
 #include "gpu/gpu_export.h"
 
 extern "C" typedef struct _ClientBuffer* ClientBuffer;
 
 namespace base {
 class Lock;
 }
 
 namespace gfx {
@@ skipping 57 matching lines @@
   // Sets a lock this will be held on every callback from the GPU
   // implementation. This lock must be set and must be held on every call into
   // the GPU implementation if it is to be used from multiple threads. This
   // may not be supported with all implementations.
   virtual void SetLock(base::Lock*) = 0;
 
   // Returns true if the channel to the Gpu is lost. When true, all contexts
   // should be considered as lost.
   virtual bool IsGpuChannelLost() = 0;
 
+  // The namespace and command buffer ID forms a unique pair for all existing
+  // GpuControl (on client) and matches for the corresponding command buffer
+  // (on server) in a single server process.
+  virtual CommandBufferNamespace GetNamespaceID() const = 0;
+  virtual uint64_t GetCommandBufferID() const = 0;
+
  private:
   DISALLOW_COPY_AND_ASSIGN(GpuControl);
 };
 
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_CLIENT_GPU_CONTROL_H_