Cleanup usage of scoped_ptr<> in remoting for C++11

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/location.h"
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 28 matching lines @@
 IqSender::~IqSender() {
   signal_strategy_->RemoveListener(this);
 }
 
 scoped_ptr<IqRequest> IqSender::SendIq(scoped_ptr<buzz::XmlElement> stanza,
                                        const ReplyCallback& callback) {
   std::string addressee = stanza->Attr(buzz::QN_TO);
   std::string id = signal_strategy_->GetNextId();
   stanza->AddAttr(buzz::QN_ID, id);
   if (!signal_strategy_->SendStanza(stanza.Pass())) {
-    return scoped_ptr<IqRequest>();
+    return nullptr;
   }
   DCHECK(requests_.find(id) == requests_.end());
   scoped_ptr<IqRequest> request(new IqRequest(this, callback, addressee));
   if (!callback.is_null())
     requests_[id] = request.get();
   return request.Pass();
 }
 
 scoped_ptr<IqRequest> IqSender::SendIq(const std::string& type,
                                        const std::string& addressee,
@@ skipping 96 matching lines @@
   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