Move Singleton and related structs to namespace base

chrome/browser/chromeos/policy/consumer_unenrollment_handler_factory.h

 // Copyright 2014 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.
 
 #ifndef CHROME_BROWSER_CHROMEOS_POLICY_CONSUMER_UNENROLLMENT_HANDLER_FACTORY_H_
 #define CHROME_BROWSER_CHROMEOS_POLICY_CONSUMER_UNENROLLMENT_HANDLER_FACTORY_H_
 
 #include "base/macros.h"
 #include "base/memory/singleton.h"
 #include "components/keyed_service/content/browser_context_keyed_service_factory.h"
 
 namespace policy {
 
 class ConsumerUnenrollmentHandler;
 
 class ConsumerUnenrollmentHandlerFactory
     : public BrowserContextKeyedServiceFactory {
  public:
   static ConsumerUnenrollmentHandler* GetForBrowserContext(
       content::BrowserContext* context);
 
   static ConsumerUnenrollmentHandlerFactory* GetInstance();
 
  private:
-  friend struct DefaultSingletonTraits<ConsumerUnenrollmentHandlerFactory>;
+  friend struct base::DefaultSingletonTraits<
+      ConsumerUnenrollmentHandlerFactory>;
 
   ConsumerUnenrollmentHandlerFactory();
   ~ConsumerUnenrollmentHandlerFactory() override;
 
   KeyedService* BuildServiceInstanceFor(
       content::BrowserContext* context) const override;
 
   DISALLOW_COPY_AND_ASSIGN(ConsumerUnenrollmentHandlerFactory);
 };
 
 }  // namespace policy
 
 #endif  // CHROME_BROWSER_CHROMEOS_POLICY_CONSUMER_UNENROLLMENT_HANDLER_FACTORY_H_