Move Singleton and related structs to namespace base

extensions/browser/extension_prefs_factory.cc

 // 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.
 
 #include "base/command_line.h"
 #include "base/prefs/pref_service.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "content/public/browser/browser_context.h"
 #include "extensions/browser/extension_pref_value_map.h"
 #include "extensions/browser/extension_pref_value_map_factory.h"
 #include "extensions/browser/extension_prefs.h"
 #include "extensions/browser/extension_prefs_factory.h"
 #include "extensions/browser/extensions_browser_client.h"
 #include "extensions/common/constants.h"
 
 namespace extensions {
 
 // static
 ExtensionPrefs* ExtensionPrefsFactory::GetForBrowserContext(
     content::BrowserContext* context) {
   return static_cast<ExtensionPrefs*>(
       GetInstance()->GetServiceForBrowserContext(context, true));
 }
 
 // static
 ExtensionPrefsFactory* ExtensionPrefsFactory::GetInstance() {
-  return Singleton<ExtensionPrefsFactory>::get();
+  return base::Singleton<ExtensionPrefsFactory>::get();
 }
 
 void ExtensionPrefsFactory::SetInstanceForTesting(
     content::BrowserContext* context,
     scoped_ptr<ExtensionPrefs> prefs) {
   Disassociate(context);
   Associate(context, prefs.Pass());
 }
 
 ExtensionPrefsFactory::ExtensionPrefsFactory()
@@ skipping 18 matching lines @@
                                     context),
       prefs_observers);
 }
 
 content::BrowserContext* ExtensionPrefsFactory::GetBrowserContextToUse(
     content::BrowserContext* context) const {
   return ExtensionsBrowserClient::Get()->GetOriginalContext(context);
 }
 
 }  // namespace extensions