base::Bind: Convert FileUtilProxy::EnsureFileExistsCallback.

webkit/fileapi/file_system_file_util_proxy.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 WEBKIT_FILEAPI_FILE_SYSTEM_FILE_UTIL_PROXY_H_
 #define WEBKIT_FILEAPI_FILE_SYSTEM_FILE_UTIL_PROXY_H_
 
 #include <vector>
 
 #include "base/callback.h"
@@ skipping 57 matching lines @@
   // |created| of the callback argument is set true and |error code|
   // is set PLATFORM_FILE_OK.
   // If the file already exists, |created| is set false and |error code|
   // is set PLATFORM_FILE_OK.
   // If the file hasn't existed but it couldn't be created for some other
   // reasons, |created| is set false and |error code| indicates the error.
   static bool EnsureFileExists(
       const FileSystemOperationContext& context,
       scoped_refptr<MessageLoopProxy> message_loop_proxy,
       const FilePath& file_path,
-      EnsureFileExistsCallback* callback);
+      const EnsureFileExistsCallback& callback);
 
   // Maps virtual file patch to its local physical location.
   static bool GetLocalPath(
       const FileSystemOperationContext& context,
       scoped_refptr<MessageLoopProxy> message_loop_proxy,
       const FilePath& virtual_path,
       GetLocalPathCallback* callback);
 
   // Retrieves the information about a file. It is invalid to pass NULL for the
   // callback.
@@ skipping 68 matching lines @@
       int64 length,
       StatusCallback* callback);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(FileSystemFileUtilProxy);
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_FILE_SYSTEM_FILE_UTIL_PROXY_H_