Move Singleton and related structs to namespace base

extensions/browser/api/web_request/web_request_api.h

 // 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.
 
 #ifndef EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_API_H_
 #define EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_API_H_
 
 #include <list>
 #include <map>
 #include <set>
@@ skipping 292 matching lines @@
   void OnOTRBrowserContextCreated(void* original_browser_context,
                                   void* otr_browser_context);
   void OnOTRBrowserContextDestroyed(void* original_browser_context,
                                     void* otr_browser_context);
 
   // Registers a |callback| that is executed when the next page load happens.
   // The callback is then deleted.
   void AddCallbackForPageLoad(const base::Closure& callback);
 
  private:
-  friend struct DefaultSingletonTraits<ExtensionWebRequestEventRouter>;
+  friend struct base::DefaultSingletonTraits<ExtensionWebRequestEventRouter>;
 
   struct EventListener;
   using EventListeners = std::vector<const EventListener*>;
   using ListenerMapForBrowserContext =
       std::map<std::string, std::set<EventListener>>;
   using ListenerMap = std::map<void*, ListenerMapForBrowserContext>;
   using BlockedRequestMap = std::map<uint64_t, BlockedRequest>;
   // Map of request_id -> bit vector of EventTypes already signaled
   using SignaledRequestMap = std::map<uint64_t, int>;
   // For each browser_context: a bool indicating whether it is an incognito
@@ skipping 228 matching lines @@
       extensions::QuotaLimitHeuristics* heuristics) const override;
   // Handle quota exceeded gracefully: Only warn the user but still execute the
   // function.
   void OnQuotaExceeded(const std::string& error) override;
   bool RunSync() override;
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_API_H_