base::Bind: Implement a 1-arity CancelableCallback and use this to implement

chrome/browser/renderer_host/offline_resource_handler.h

 // Copyright (c) 2011 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 CHROME_BROWSER_RENDERER_HOST_OFFLINE_RESOURCE_HANDLER_H_
 #define CHROME_BROWSER_RENDERER_HOST_OFFLINE_RESOURCE_HANDLER_H_
 #pragma once
 
 #include <string>
 
@@ skipping 34 matching lines @@
   virtual bool OnReadCompleted(int request_id, int* bytes_read) OVERRIDE;
   virtual bool OnResponseCompleted(int request_id,
                                    const net::URLRequestStatus& status,
                                    const std::string& security_info) OVERRIDE;
   virtual void OnRequestClosed() OVERRIDE;
 
   // OfflineLoadPage callback.
   void OnBlockingPageComplete(bool proceed);
 
  private:
-  // Erase the state assocaited with a deferred load request.
+  // Erase the state associated with a deferred load request.
   void ClearRequestInfo();
   bool IsRemote(const GURL& url) const;
 
   // Resume the deferred load request.
   void Resume();
 
   // True if chrome should show the offline page.
   bool ShouldShowOfflinePage(const GURL& url) const;
 
   // Shows the offline interstitial page on the UI thread.
   void ShowOfflinePage();
 
   // A callback to tell if an appcache exists.
   void OnCanHandleOfflineComplete(int rv);
 
   scoped_refptr<ResourceHandler> next_handler_;
 
   int process_host_id_;
   int render_view_id_;
   ResourceDispatcherHost* rdh_;
   net::URLRequest* request_;
   ChromeAppCacheService* const appcache_service_;
 
   // The state for deferred load quest.
   int deferred_request_id_;
   GURL deferred_url_;
 
-  scoped_refptr<net::CancelableOldCompletionCallback<OfflineResourceHandler> >
-      appcache_completion_callback_;
+  net::CancelableCompletionCallback appcache_completion_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(OfflineResourceHandler);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_OFFLINE_RESOURCE_HANDLER_H_