Remove DeleteTask and convert remaining users.

content/browser/chrome_blob_storage_context.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_CHROME_BLOB_STORAGE_CONTEXT_H_
 #define CONTENT_BROWSER_CHROME_BLOB_STORAGE_CONTEXT_H_
 #pragma once
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/message_loop_helpers.h"
 #include "content/common/content_export.h"
 #include "content/public/browser/browser_thread.h"
 
 namespace webkit_blob {
 class BlobStorageController;
 }
 
 // A context class that keeps track of BlobStorageController used by the chrome.
 // There is an instance associated with each BrowserContext. There could be
 // multiple URLRequestContexts in the same browser context that refers to the
@@ skipping 10 matching lines @@
   void InitializeOnIOThread();
 
   webkit_blob::BlobStorageController* controller() const {
     return controller_.get();
   }
 
  private:
   friend class base::RefCountedThreadSafe<
       ChromeBlobStorageContext, content::BrowserThread::DeleteOnIOThread>;
   friend class content::BrowserThread;
-  friend class DeleteTask<ChromeBlobStorageContext>;
+  friend class base::DeleteHelper<ChromeBlobStorageContext>;
 
   virtual ~ChromeBlobStorageContext();
 
   scoped_ptr<webkit_blob::BlobStorageController> controller_;
 };
 
 #endif  // CONTENT_BROWSER_CHROME_BLOB_STORAGE_CONTEXT_H_