Move Singleton and related structs to namespace base

extensions/browser/guest_view/mime_handler_view/mime_handler_stream_manager.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 "extensions/browser/guest_view/mime_handler_view/mime_handler_stream_manager.h"
 
 #include "base/memory/singleton.h"
 #include "components/keyed_service/content/browser_context_dependency_manager.h"
 #include "components/keyed_service/content/browser_context_keyed_service_factory.h"
 #include "content/public/browser/render_frame_host.h"
@@ skipping 22 matching lines @@
 
 MimeHandlerStreamManagerFactory::MimeHandlerStreamManagerFactory()
     : BrowserContextKeyedServiceFactory(
           "MimeHandlerStreamManager",
           BrowserContextDependencyManager::GetInstance()) {
 }
 
 // static
 MimeHandlerStreamManagerFactory*
 MimeHandlerStreamManagerFactory::GetInstance() {
-  return Singleton<MimeHandlerStreamManagerFactory>::get();
+  return base::Singleton<MimeHandlerStreamManagerFactory>::get();
 }
 
 MimeHandlerStreamManager* MimeHandlerStreamManagerFactory::Get(
     content::BrowserContext* context) {
   return static_cast<MimeHandlerStreamManager*>(
       GetServiceForBrowserContext(context, true));
 }
 
 KeyedService* MimeHandlerStreamManagerFactory::BuildServiceInstanceFor(
     content::BrowserContext* context) const {
@@ skipping 143 matching lines @@
   stream_manager_->ReleaseStream(view_id_);
 }
 
 bool MimeHandlerStreamManager::EmbedderObserver::IsTrackedRenderFrameHost(
     content::RenderFrameHost* render_frame_host) {
   return render_frame_host->GetRoutingID() == render_frame_id_ &&
          render_frame_host->GetProcess()->GetID() == render_process_id_;
 }
 
 }  // namespace extensions