Move Singleton and related structs to namespace base

chrome/browser/signin/account_fetcher_service_factory.cc

 // Copyright 2015 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/signin/account_fetcher_service_factory.h"
 
 #include "chrome/browser/invalidation/profile_invalidation_provider_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/account_tracker_service_factory.h"
 #include "chrome/browser/signin/chrome_signin_client_factory.h"
@@ skipping 18 matching lines @@
 
 // static
 AccountFetcherService* AccountFetcherServiceFactory::GetForProfile(
     Profile* profile) {
   return static_cast<AccountFetcherService*>(
       GetInstance()->GetServiceForBrowserContext(profile, true));
 }
 
 // static
 AccountFetcherServiceFactory* AccountFetcherServiceFactory::GetInstance() {
-  return Singleton<AccountFetcherServiceFactory>::get();
+  return base::Singleton<AccountFetcherServiceFactory>::get();
 }
 
 void AccountFetcherServiceFactory::RegisterProfilePrefs(
     user_prefs::PrefRegistrySyncable* registry) {
   AccountFetcherService::RegisterPrefs(registry);
 }
 
 KeyedService* AccountFetcherServiceFactory::BuildServiceInstanceFor(
     content::BrowserContext* context) const {
   Profile* profile = Profile::FromBrowserContext(context);
   AccountFetcherService* service = new AccountFetcherService();
   invalidation::ProfileInvalidationProvider* invalidation_provider =
       invalidation::ProfileInvalidationProviderFactory::GetForProfile(profile);
   // Chrome OS login and guest profiles do not support invalidation. This is
   // fine as they do not have GAIA credentials anyway. http://crbug.com/358169
   invalidation::InvalidationService* invalidation_service =
       invalidation_provider ? invalidation_provider->GetInvalidationService()
                             : nullptr;
   service->Initialize(ChromeSigninClientFactory::GetForProfile(profile),
                       ProfileOAuth2TokenServiceFactory::GetForProfile(profile),
                       AccountTrackerServiceFactory::GetForProfile(profile),
                       invalidation_service);
   return service;
 }