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

remoting/host/cast_extension_session.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/host/cast_extension_session.h"
 
 #include "base/bind.h"
 #include "base/json/json_reader.h"
 #include "base/json/json_writer.h"
 #include "base/logging.h"
@@ skipping 167 matching lines @@
     scoped_refptr<net::URLRequestContextGetter> url_request_context_getter,
     const protocol::NetworkSettings& network_settings,
     ClientSessionControl* client_session_control,
     protocol::ClientStub* client_stub) {
   scoped_ptr<CastExtensionSession> cast_extension_session(
       new CastExtensionSession(caller_task_runner,
                                url_request_context_getter,
                                network_settings,
                                client_session_control,
                                client_stub));
-  if (!cast_extension_session->WrapTasksAndSave()) {
-    return scoped_ptr<CastExtensionSession>();
-  }
-  if (!cast_extension_session->InitializePeerConnection()) {
-    return scoped_ptr<CastExtensionSession>();
+  if (!cast_extension_session->WrapTasksAndSave() ||
+      !cast_extension_session->InitializePeerConnection()) {
+    return nullptr;
   }
   return cast_extension_session.Pass();
 }
 
 void CastExtensionSession::OnCreateSessionDescription(
     webrtc::SessionDescriptionInterface* desc) {
   if (!caller_task_runner_->BelongsToCurrentThread()) {
     caller_task_runner_->PostTask(
         FROM_HERE,
         base::Bind(&CastExtensionSession::OnCreateSessionDescription,
@@ skipping 460 matching lines @@
   json->SetString(kWebRtcCandidate, candidate_str);
   std::string json_str;
   if (!base::JSONWriter::Write(json.get(), &json_str)) {
     LOG(ERROR) << "Failed to serialize candidate message.";
     return;
   }
   SendMessageToClient(kSubjectNewCandidate, json_str);
 }
 
 }  // namespace remoting