Refactor MHTMLGenerator to allow getting sending the data to a file descriptor.

chrome/browser/extensions/api/page_capture/page_capture_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 CHROME_BROWSER_EXTENSIONS_API_PAGE_CAPTURE_PAGE_CAPTURE_API_H_
 #define CHROME_BROWSER_EXTENSIONS_API_PAGE_CAPTURE_PAGE_CAPTURE_API_H_
 
 #include <string>
 
 #include "base/memory/ref_counted.h"
@@ skipping 32 matching lines @@
 
   // Called on the file thread.
   void CreateTemporaryFile();
 
   // Called on the UI thread.
   void TemporaryFileCreated(bool success);
   void ReturnFailure(const std::string& error);
   void ReturnSuccess(int64 file_size);
 
   // Callback called once the MHTML generation is done.
-  void MHTMLGenerated(const base::FilePath& file_path, int64 mhtml_file_size);
+  void MHTMLGenerated(int64 mhtml_file_size);
 
   // Returns the WebContents we are associated with, NULL if it's been closed.
   content::WebContents* GetWebContents();
 
   scoped_ptr<extensions::api::page_capture::SaveAsMHTML::Params> params_;
 
   // The path to the temporary file containing the MHTML data.
   base::FilePath mhtml_path_;
 
   // The file containing the MHTML.
   scoped_refptr<webkit_blob::ShareableFileReference> mhtml_file_;
 
   DECLARE_EXTENSION_FUNCTION("pageCapture.saveAsMHTML", PAGECAPTURE_SAVEASMHTML)
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_API_PAGE_CAPTURE_PAGE_CAPTURE_API_H_