gdata: Convert FindEntryByResourceIdSync() to asynchronous.

chrome/browser/chromeos/gdata/find_entry_callback.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_CHROMEOS_GDATA_FIND_ENTRY_CALLBACK_H_
-#define CHROME_BROWSER_CHROMEOS_GDATA_FIND_ENTRY_CALLBACK_H_
-#pragma once
-
-#include "base/callback.h"
-#include "base/platform_file.h"
-
-namespace gdata {
-
-class GDataEntry;
-
-// Used to get result of file search. Please note that |file| is a live
-// object provided to this callback under lock. It must not be used outside
-// of the callback method. This callback can be invoked on different thread
-// than one that started the request.
-typedef base::Callback<void(base::PlatformFileError error, GDataEntry* entry)>
-    FindEntryCallback;
-
-// Callback used to find a directory element for file system updates.
-void ReadOnlyFindEntryCallback(GDataEntry** out,
-                               base::PlatformFileError error,
-                               GDataEntry* entry);
-
-}  // namespace gdata
-
-#endif  // CHROME_BROWSER_CHROMEOS_GDATA_FIND_ENTRY_CALLBACK_H_