Use base::ResetAndReturn() in remoting.

remoting/signaling/iq_sender.cc

 // Copyright 2014 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 "remoting/signaling/iq_sender.h"
 
 #include "base/bind.h"
+#include "base/callback_helpers.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "remoting/signaling/signal_strategy.h"
 #include "third_party/webrtc/libjingle/xmllite/xmlelement.h"
 #include "third_party/webrtc/libjingle/xmpp/constants.h"
@@ skipping 113 matching lines @@
 IqRequest::~IqRequest() {
   sender_->RemoveRequest(this);
 }
 
 void IqRequest::SetTimeout(base::TimeDelta timeout) {
   base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
       FROM_HERE, base::Bind(&IqRequest::OnTimeout, AsWeakPtr()), timeout);
 }
 
 void IqRequest::CallCallback(const buzz::XmlElement* stanza) {
-  if (!callback_.is_null()) {
-    IqSender::ReplyCallback callback(callback_);
-    callback_.Reset();
-    callback.Run(this, stanza);
-  }
+  if (!callback_.is_null())
+    base::ResetAndReturn(&callback_).Run(this, stanza);
 }
 
 void IqRequest::OnTimeout() {
   CallCallback(nullptr);
 }
 
 void IqRequest::OnResponse(const buzz::XmlElement* stanza) {
   // It's unsafe to delete signal strategy here, and the callback may
   // want to do that, so we post task to invoke the callback later.
   scoped_ptr<buzz::XmlElement> stanza_copy(new buzz::XmlElement(*stanza));
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&IqRequest::DeliverResponse, AsWeakPtr(),
                             base::Passed(&stanza_copy)));
 }
 
 void IqRequest::DeliverResponse(scoped_ptr<buzz::XmlElement> stanza) {
   CallCallback(stanza.get());
 }
 
 }  // namespace remoting