Eliminate implicit conversion from scoped_refptr<T> to T*

ppapi/proxy/plugin_globals.cc

 // 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.
 
 #include "ppapi/proxy/plugin_globals.h"
 
 #include "ppapi/proxy/plugin_dispatcher.h"
 
 namespace ppapi {
 namespace proxy {
@@ skipping 21 matching lines @@
 }
 
 ResourceTracker* PluginGlobals::GetResourceTracker() {
   return &plugin_resource_tracker_;
 }
 
 VarTracker* PluginGlobals::GetVarTracker() {
   return &plugin_var_tracker_;
 }
 
-CallbackTracker* PluginGlobals::GetCallbackTrackerForInstance(
+scoped_refptr<CallbackTracker> PluginGlobals::GetCallbackTrackerForInstance(
     PP_Instance instance) {
   // In the plugin process, the callback tracker is always the same, regardless
   // of the instance.
-  return callback_tracker_.get();
+  return callback_tracker_;
 }
 
 FunctionGroupBase* PluginGlobals::GetFunctionAPI(PP_Instance inst, ApiID id) {
   PluginDispatcher* dispatcher = PluginDispatcher::GetForInstance(inst);
   if (dispatcher)
     return dispatcher->GetFunctionAPI(id);
   return NULL;
 }
 
 PP_Module PluginGlobals::GetModuleForInstance(PP_Instance instance) {
   // Currently proxied plugins don't use the PP_Module for anything useful.
   return 0;
 }
 
 base::Lock* PluginGlobals::GetProxyLock() {
 #ifdef ENABLE_PEPPER_THREADING
   return &proxy_lock_;
 #else
   return NULL;
 #endif
 }
 
 bool PluginGlobals::IsPluginGlobals() const {
   return true;
 }
 
 }  // namespace proxy
 }  // namespace ppapi