Make OAuth2TokenService and subclasses take delegate by unique_ptr

chrome/browser/chromeos/settings/device_oauth2_token_service_factory.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 "chrome/browser/chromeos/settings/device_oauth2_token_service_factory.h"
 
+#include "base/memory/ptr_util.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/settings/device_oauth2_token_service.h"
 #include "chrome/browser/chromeos/settings/device_oauth2_token_service_delegate.h"
 #include "chrome/browser/chromeos/settings/token_encryptor.h"
 #include "chromeos/cryptohome/system_salt_getter.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace chromeos {
 
 namespace {
 
 static DeviceOAuth2TokenService* g_device_oauth2_token_service_ = NULL;
 
 }  // namespace
 
 // static
 DeviceOAuth2TokenService* DeviceOAuth2TokenServiceFactory::Get() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   return g_device_oauth2_token_service_;
 }
 
 // static
 void DeviceOAuth2TokenServiceFactory::Initialize() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   DCHECK(!g_device_oauth2_token_service_);
-  g_device_oauth2_token_service_ =
-      new DeviceOAuth2TokenService(new DeviceOAuth2TokenServiceDelegate(
+  g_device_oauth2_token_service_ = new DeviceOAuth2TokenService(
+      base::MakeUnique<DeviceOAuth2TokenServiceDelegate>(
           g_browser_process->system_request_context(),
           g_browser_process->local_state()));
 }
 
 // static
 void DeviceOAuth2TokenServiceFactory::Shutdown() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   if (g_device_oauth2_token_service_) {
     delete g_device_oauth2_token_service_;
     g_device_oauth2_token_service_ = NULL;
   }
 }
 
 }  // namespace chromeos