(For-try) Divide recursive Copy/Move into multiple async tasks

webkit/fileapi/media/native_media_file_util.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_MEDIA_NATIVE_MEDIA_FILE_UTIL_H_
 #define WEBKIT_FILEAPI_MEDIA_NATIVE_MEDIA_FILE_UTIL_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "webkit/fileapi/isolated_file_util.h"
 #include "webkit/storage/webkit_storage_export.h"
@@ skipping 23 matching lines @@
       bool recursive) OVERRIDE;
   virtual base::PlatformFileError Touch(
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       const base::Time& last_access_time,
       const base::Time& last_modified_time) OVERRIDE;
   virtual base::PlatformFileError Truncate(
       FileSystemOperationContext* context,
       const FileSystemURL& url,
       int64 length) OVERRIDE;
-  virtual bool IsDirectoryEmpty(
-      FileSystemOperationContext* context,
-      const FileSystemURL& url) OVERRIDE;
   virtual base::PlatformFileError CopyOrMoveFile(
       FileSystemOperationContext* context,
       const FileSystemURL& src_url,
       const FileSystemURL& dest_url,
       bool copy) OVERRIDE;
   virtual base::PlatformFileError CopyInForeignFile(
         FileSystemOperationContext* context,
         const FilePath& src_file_path,
         const FileSystemURL& dest_url) OVERRIDE;
   virtual base::PlatformFileError DeleteFile(
@@ skipping 25 matching lines @@
       const FileSystemURL& file_system_url,
       base::PlatformFileError failure_error,
       FilePath* local_file_path);
 
   DISALLOW_COPY_AND_ASSIGN(NativeMediaFileUtil);
 };
 
 }  // namespace fileapi
 
 #endif  // WEBKIT_FILEAPI_MEDIA_NATIVE_MEDIA_FILE_UTIL_H_