Move Singleton and related structs to namespace base

chrome/browser/ui/ash/app_sync_ui_state_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/ui/ash/app_sync_ui_state_factory.h"
 
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sync/profile_sync_service_factory.h"
 #include "chrome/browser/ui/ash/app_sync_ui_state.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "extensions/browser/extension_registry_factory.h"
 
 // static
 AppSyncUIState* AppSyncUIStateFactory::GetForProfile(Profile* profile) {
   if (!AppSyncUIState::ShouldObserveAppSyncForProfile(profile))
     return NULL;
 
   return static_cast<AppSyncUIState*>(
       GetInstance()->GetServiceForBrowserContext(profile, true));
 }
 
 // static
 AppSyncUIStateFactory* AppSyncUIStateFactory::GetInstance() {
-  return Singleton<AppSyncUIStateFactory>::get();
+  return base::Singleton<AppSyncUIStateFactory>::get();
 }
 
 AppSyncUIStateFactory::AppSyncUIStateFactory()
     : BrowserContextKeyedServiceFactory(
         "AppSyncUIState",
         BrowserContextDependencyManager::GetInstance()) {
   DependsOn(extensions::ExtensionRegistryFactory::GetInstance());
   DependsOn(ProfileSyncServiceFactory::GetInstance());
 }
 
 AppSyncUIStateFactory::~AppSyncUIStateFactory() {
 }
 
 KeyedService* AppSyncUIStateFactory::BuildServiceInstanceFor(
     content::BrowserContext* context) const {
   Profile* profile = static_cast<Profile*>(context);
   DCHECK(AppSyncUIState::ShouldObserveAppSyncForProfile(profile));
   return new AppSyncUIState(profile);
 }