Move Singleton and related structs to namespace base

chrome/browser/autocomplete/shortcuts_backend_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/autocomplete/shortcuts_backend_factory.h"
 
 #include "base/memory/scoped_ptr.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/autocomplete/shortcuts_extensions_manager.h"
 #include "chrome/browser/history/history_service_factory.h"
@@ skipping 20 matching lines @@
 
 // static
 scoped_refptr<ShortcutsBackend> ShortcutsBackendFactory::GetForProfileIfExists(
     Profile* profile) {
   return static_cast<ShortcutsBackend*>(
       GetInstance()->GetServiceForBrowserContext(profile, false).get());
 }
 
 // static
 ShortcutsBackendFactory* ShortcutsBackendFactory::GetInstance() {
-  return Singleton<ShortcutsBackendFactory>::get();
+  return base::Singleton<ShortcutsBackendFactory>::get();
 }
 
 // static
 scoped_refptr<RefcountedKeyedService>
 ShortcutsBackendFactory::BuildProfileForTesting(
     content::BrowserContext* profile) {
   return CreateShortcutsBackend(Profile::FromBrowserContext(profile), false);
 }
 
 // static
@@ skipping 44 matching lines @@
       content::BrowserThread::GetMessageLoopProxyForThread(
           content::BrowserThread::DB),
       profile->GetPath().Append(kShortcutsDatabaseName), suppress_db));
 #if defined(ENABLE_EXTENSIONS)
   ShortcutsExtensionsManager* extensions_manager =
       new ShortcutsExtensionsManager(profile);
   profile->SetUserData(kShortcutsExtensionsManagerKey, extensions_manager);
 #endif
   return backend->Init() ? backend : nullptr;
 }