Refactor FileSystemOperation to take callback for each method.

webkit/fileapi/file_system_dir_url_request_job.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 WEBKIT_FILEAPI_FILE_SYSTEM_DIR_URL_REQUEST_JOB_H_
 #define WEBKIT_FILEAPI_FILE_SYSTEM_DIR_URL_REQUEST_JOB_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 29 matching lines @@
   virtual bool GetMimeType(std::string* mime_type) const OVERRIDE;
   // TODO(adamk): Implement GetResponseInfo and GetResponseCode to simulate
   // an HTTP response.
 
  private:
   class CallbackDispatcher;
 
   virtual ~FileSystemDirURLRequestJob();
 
   void StartAsync();
-  void DidReadDirectory(const std::vector<base::FileUtilProxy::Entry>& entries,
+  void DidReadDirectory(base::PlatformFileError result,
+                        const std::vector<base::FileUtilProxy::Entry>& entries,
                         bool has_more);
   FileSystemOperationInterface* GetNewOperation(const GURL& url);
 
   std::string data_;
   FileSystemContext* file_system_context_;
   scoped_refptr<base::MessageLoopProxy> file_thread_proxy_;
   base::WeakPtrFactory<FileSystemDirURLRequestJob> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(FileSystemDirURLRequestJob);
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_FILE_SYSTEM_DIR_URL_REQUEST_JOB_H_