Move Singleton and related structs to namespace base

apps/saved_files_service_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 "apps/saved_files_service_factory.h"
 
 #include "apps/saved_files_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 
 namespace apps {
 
 // static
 SavedFilesService* SavedFilesServiceFactory::GetForProfile(Profile* profile) {
   return static_cast<SavedFilesService*>(
       GetInstance()->GetServiceForBrowserContext(profile, true));
 }
 
 // static
 SavedFilesServiceFactory* SavedFilesServiceFactory::GetInstance() {
-  return Singleton<SavedFilesServiceFactory>::get();
+  return base::Singleton<SavedFilesServiceFactory>::get();
 }
 
 SavedFilesServiceFactory::SavedFilesServiceFactory()
     : BrowserContextKeyedServiceFactory(
           "SavedFilesService",
           BrowserContextDependencyManager::GetInstance()) {}
 
 SavedFilesServiceFactory::~SavedFilesServiceFactory() {}
 
 KeyedService* SavedFilesServiceFactory::BuildServiceInstanceFor(
     content::BrowserContext* profile) const {
   return new SavedFilesService(static_cast<Profile*>(profile));
 }
 
 }  // namespace apps