Update ppapi/ to use scoped_refptr<T>::get() rather than implicit "operator T*"

ppapi/shared_impl/thread_aware_callback.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/shared_impl/thread_aware_callback.h"
 
 #include "base/callback.h"
 #include "base/logging.h"
 #include "ppapi/shared_impl/ppapi_globals.h"
 #include "ppapi/shared_impl/ppb_message_loop_shared.h"
@@ skipping 31 matching lines @@
   core_->MarkAsAborted();
 }
 
 // static
 bool ThreadAwareCallbackBase::HasTargetLoop() {
   return !!PpapiGlobals::Get()->GetCurrentMessageLoop();
 }
 
 void ThreadAwareCallbackBase::InternalRunOnTargetThread(
     const base::Closure& closure) {
-  if (target_loop_ != PpapiGlobals::Get()->GetCurrentMessageLoop()) {
+  if (target_loop_.get() != PpapiGlobals::Get()->GetCurrentMessageLoop()) {
     target_loop_->PostClosure(
         FROM_HERE,
         RunWhileLocked(base::Bind(&Core::RunIfNotAborted, core_, closure)),
         0);
   } else {
     CallWhileUnlocked(closure);
   }
 }
 
 }  // namespace internal
 }  // namespace ppapi