Use base::ResetAndReturn() in remoting.

remoting/host/register_support_host_request.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 "remoting/host/register_support_host_request.h"
 
 #include "base/bind.h"
+#include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/time/time.h"
 #include "remoting/base/constants.h"
 #include "remoting/host/host_config.h"
 #include "remoting/signaling/iq_sender.h"
 #include "remoting/signaling/signal_strategy.h"
 #include "third_party/webrtc/libjingle/xmllite/xmlelement.h"
 #include "third_party/webrtc/libjingle/xmpp/constants.h"
@@ skipping 153 matching lines @@
 }
 
 void RegisterSupportHostRequest::CallCallback(
     bool success, const std::string& support_id, base::TimeDelta lifetime) {
   // Cleanup state before calling the callback.
   request_.reset();
   iq_sender_.reset();
   signal_strategy_->RemoveListener(this);
   signal_strategy_ = nullptr;
 
-  RegisterCallback callback = callback_;
-  callback_.Reset();
-  callback.Run(success, support_id, lifetime);
+  base::ResetAndReturn(&callback_).Run(success, support_id, lifetime);
 }
 
 }  // namespace remoting