Remove DeleteTask and convert remaining users.

content/browser/appcache/chrome_appcache_service.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 CONTENT_BROWSER_APPCACHE_CHROME_APPCACHE_SERVICE_H_
 #define CONTENT_BROWSER_APPCACHE_CHROME_APPCACHE_SERVICE_H_
 #pragma once
 
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
+#include "base/message_loop_helpers.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "webkit/appcache/appcache_policy.h"
 #include "webkit/appcache/appcache_service.h"
 #include "webkit/quota/special_storage_policy.h"
 
 class FilePath;
 
@@ skipping 24 matching lines @@
   void InitializeOnIOThread(
       const FilePath& cache_path,  // may be empty to use in-memory structures
       const content::ResourceContext* resource_context,
       scoped_refptr<quota::SpecialStoragePolicy> special_storage_policy);
 
  private:
   friend class base::RefCountedThreadSafe<
       ChromeAppCacheService,
       content::BrowserThread::DeleteOnIOThread>;
   friend class content::BrowserThread;
-  friend class DeleteTask<ChromeAppCacheService>;
+  friend class base::DeleteHelper<ChromeAppCacheService>;
 
   virtual ~ChromeAppCacheService();
 
   // AppCachePolicy overrides
   virtual bool CanLoadAppCache(const GURL& manifest_url,
                                const GURL& first_party) OVERRIDE;
   virtual bool CanCreateAppCache(const GURL& manifest_url,
                                  const GURL& first_party) OVERRIDE;
 
   // content::NotificationObserver override
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
   const content::ResourceContext* resource_context_;
   content::NotificationRegistrar registrar_;
   FilePath cache_path_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeAppCacheService);
 };
 
 #endif  // CONTENT_BROWSER_APPCACHE_CHROME_APPCACHE_SERVICE_H_