Move Singleton and related structs to namespace base

chrome/browser/chromeos/extensions/install_limiter_factory.cc

 // Copyright (c) 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/chromeos/extensions/install_limiter_factory.h"
 
 #include "chrome/browser/chromeos/extensions/install_limiter.h"
 #include "chrome/browser/profiles/profile.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "extensions/browser/extension_system_provider.h"
 #include "extensions/browser/extensions_browser_client.h"
 
 namespace extensions {
 
 // static
 InstallLimiter* InstallLimiterFactory::GetForProfile(Profile* profile) {
   return static_cast<InstallLimiter*>(
       GetInstance()->GetServiceForBrowserContext(profile, true));
 }
 
 // static
 InstallLimiterFactory* InstallLimiterFactory::GetInstance() {
-  return Singleton<InstallLimiterFactory>::get();
+  return base::Singleton<InstallLimiterFactory>::get();
 }
 
 InstallLimiterFactory::InstallLimiterFactory()
     : BrowserContextKeyedServiceFactory(
         "InstallLimiter",
         BrowserContextDependencyManager::GetInstance()) {
   DependsOn(ExtensionsBrowserClient::Get()->GetExtensionSystemFactory());
 }
 
 InstallLimiterFactory::~InstallLimiterFactory() {
 }
 
 KeyedService* InstallLimiterFactory::BuildServiceInstanceFor(
     content::BrowserContext* profile) const {
   return new InstallLimiter();
 }
 
 }  // namespace extensions