Move Singleton and related structs to namespace base

chrome/browser/local_discovery/privet_notifications_factory.cc

 // Copyright 2013 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/local_discovery/privet_notifications_factory.h"
 
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/local_discovery/privet_notifications.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 
 namespace local_discovery {
 
 PrivetNotificationServiceFactory*
 PrivetNotificationServiceFactory::GetInstance() {
-  return Singleton<PrivetNotificationServiceFactory>::get();
+  return base::Singleton<PrivetNotificationServiceFactory>::get();
 }
 
 PrivetNotificationServiceFactory::PrivetNotificationServiceFactory()
     : BrowserContextKeyedServiceFactory(
         "PrivetNotificationService",
         BrowserContextDependencyManager::GetInstance()) {
 }
 
 PrivetNotificationServiceFactory::~PrivetNotificationServiceFactory() {
 }
 
 KeyedService* PrivetNotificationServiceFactory::BuildServiceInstanceFor(
     content::BrowserContext* profile) const {
   return new PrivetNotificationService(profile);
 }
 
 bool
 PrivetNotificationServiceFactory::ServiceIsCreatedWithBrowserContext() const {
   return PrivetNotificationService::IsEnabled();
 }
 
 bool PrivetNotificationServiceFactory::ServiceIsNULLWhileTesting() const {
   return true;
 }
 
 }  // namespace local_discovery