Eliminate implicit conversion from scoped_refptr<T> to T*

webkit/plugins/ppapi/host_globals.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 WEBKIT_PLUGINS_PPAPI_HOST_GLOBALS_H_
 #define WEBKIT_PLUGINS_PPAPI_HOST_GLOBALS_H_
 
 #include "base/compiler_specific.h"
 #include "ppapi/shared_impl/callback_tracker.h"
 #include "ppapi/shared_impl/ppapi_globals.h"
@@ skipping 18 matching lines @@
   // PpapiGlobals::Get() when possible. Use this only when you need some
   // host-specific functionality.
   inline static HostGlobals* Get() {
     DCHECK(PpapiGlobals::Get()->IsHostGlobals());
     return static_cast<HostGlobals*>(PpapiGlobals::Get());
   }
 
   // PpapiGlobals implementation.
   virtual ::ppapi::ResourceTracker* GetResourceTracker() OVERRIDE;
   virtual ::ppapi::VarTracker* GetVarTracker() OVERRIDE;
-  virtual ::ppapi::CallbackTracker* GetCallbackTrackerForInstance(
-      PP_Instance instance) OVERRIDE;
+  virtual scoped_refptr< ::ppapi::CallbackTracker>
+  GetCallbackTrackerForInstance(PP_Instance instance) OVERRIDE;
   virtual ::ppapi::FunctionGroupBase* GetFunctionAPI(
       PP_Instance inst,
       ::ppapi::ApiID id) OVERRIDE;
   virtual PP_Module GetModuleForInstance(PP_Instance instance) OVERRIDE;
   virtual base::Lock* GetProxyLock() OVERRIDE;
 
   HostVarTracker* host_var_tracker() {
     return &host_var_tracker_;
   }
 
@@ skipping 49 matching lines @@
   typedef std::map<PP_Module, PluginModule*> ModuleMap;
   ModuleMap module_map_;
 
   DISALLOW_COPY_AND_ASSIGN(HostGlobals);
 };
 
 }  // namespace ppapi
 }  // namespace webkit
 
 #endif   // WEBKIT_PLUGINS_PPAPI_HOST_GLOBALS_H_