Restore KeyedServiceFactory diagnostics for context use-after-destroy.

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 <stdint.h>
 
 #include <list>
@@ skipping 54 matching lines @@
 // extensions::EventRouter to deal with event listeners. There is one instance
 // per BrowserContext which is shared with incognito.
 class WebRequestAPI : public BrowserContextKeyedAPI,
                       public EventRouter::Observer {
  public:
   explicit WebRequestAPI(content::BrowserContext* context);
   ~WebRequestAPI() override;
 
   // BrowserContextKeyedAPI support:
   static BrowserContextKeyedAPIFactory<WebRequestAPI>* GetFactoryInstance();
+  void Shutdown() override;
 
   // EventRouter::Observer overrides:
   void OnListenerRemoved(const EventListenerInfo& details) override;
 
  private:
   friend class BrowserContextKeyedAPIFactory<WebRequestAPI>;
 
   // BrowserContextKeyedAPI support:
   static const char* service_name() { return "WebRequestAPI"; }
   static const bool kServiceRedirectedInIncognito = true;
@@ skipping 534 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;
   ResponseAction Run() override;
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_BROWSER_API_WEB_REQUEST_WEB_REQUEST_API_H_