Move Singleton and related structs to namespace base

chrome/browser/media_galleries/media_galleries_preferences_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/media_galleries/media_galleries_preferences_factory.h"
 
 #include "chrome/browser/media_galleries/media_galleries_preferences.h"
 #include "chrome/browser/profiles/incognito_helpers.h"
 #include "chrome/browser/profiles/profile.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/pref_registry/pref_registry_syncable.h"
 
 // static
 MediaGalleriesPreferences*
 MediaGalleriesPreferencesFactory::GetForProfile(Profile* profile) {
   return static_cast<MediaGalleriesPreferences*>(
       GetInstance()->GetServiceForBrowserContext(profile, true));
 }
 
 // static
 MediaGalleriesPreferencesFactory*
 MediaGalleriesPreferencesFactory::GetInstance() {
-  return Singleton<MediaGalleriesPreferencesFactory>::get();
+  return base::Singleton<MediaGalleriesPreferencesFactory>::get();
 }
 
 MediaGalleriesPreferencesFactory::MediaGalleriesPreferencesFactory()
     : BrowserContextKeyedServiceFactory(
         "MediaGalleriesPreferences",
         BrowserContextDependencyManager::GetInstance()) {}
 
 MediaGalleriesPreferencesFactory::~MediaGalleriesPreferencesFactory() {}
 
 KeyedService* MediaGalleriesPreferencesFactory::BuildServiceInstanceFor(
     content::BrowserContext* profile) const {
   return new MediaGalleriesPreferences(static_cast<Profile*>(profile));
 }
 
 void MediaGalleriesPreferencesFactory::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* prefs) {
   MediaGalleriesPreferences::RegisterProfilePrefs(prefs);
 }
 
 content::BrowserContext*
 MediaGalleriesPreferencesFactory::GetBrowserContextToUse(
     content::BrowserContext* context) const {
   return chrome::GetBrowserContextRedirectedInIncognito(context);
 }