Make a global enum to differentiate impl & proxy.

webkit/plugins/ppapi/mock_resource.h

 // Copyright (c) 2011 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 WEBKIT_PLUGINS_PPAPI_MOCK_RESOURCE_H_
 #define WEBKIT_PLUGINS_PPAPI_MOCK_RESOURCE_H_
 
 #include "ppapi/shared_impl/resource.h"
 
 namespace webkit {
 namespace ppapi {
 
 // Tests can derive from this to implement special test-specific resources.
 // It's assumed that a test will only need one mock resource, so it can
 // static_cast to get its own implementation.
 class MockResource : public ::ppapi::Resource {
  public:
-  MockResource(PP_Instance instance) : Resource(instance) {}
+  MockResource(PP_Instance instance)
+      : Resource(::ppapi::OBJECT_IS_IMPL, instance) {}
   virtual ~MockResource() {}
 };
 
 }  // namespace ppapi
 }  // namespace webkit
 
 #endif  // WEBKIT_PLUGINS_PPAPI_MOCK_RESOURCE_H_