Add support for GL_CHROMIUM_pixel_transfer_buffer_object.

gpu/command_buffer/service/common_decoder.h

Index: gpu/command_buffer/service/common_decoder.h
diff --git a/gpu/command_buffer/service/common_decoder.h b/gpu/command_buffer/service/common_decoder.h
index 1b8cf3882a646482d6d0899b46e9c7a81d6c878e..6047be906e750a26643407a52d915ae01773ad57 100644
--- a/gpu/command_buffer/service/common_decoder.h
+++ b/gpu/command_buffer/service/common_decoder.h
@@ -10,6 +10,7 @@
 #include <string>
 #include "base/memory/linked_ptr.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
 #include "gpu/command_buffer/service/cmd_parser.h"
 #include "gpu/gpu_export.h"
 
@@ -19,7 +20,8 @@ class CommandBufferEngine;
 
 // This class is a helper base class for implementing the common parts of the
 // o3d/gl2 command buffer decoder.
-class GPU_EXPORT CommonDecoder : NON_EXPORTED_BASE(public AsyncAPIInterface) {
+class GPU_EXPORT CommonDecoder : public base::SupportsWeakPtr<CommonDecoder>,
+                                 NON_EXPORTED_BASE(public AsyncAPIInterface) {
  public:
   typedef error::Error Error;