gdata: Convert FindEntryByResourceIdSync() to asynchronous.

chrome/browser/chromeos/gdata/gdata_params.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_GDATA_PARAMS_H_
 #define CHROME_BROWSER_CHROMEOS_GDATA_GDATA_PARAMS_H_
 #pragma once
 
 #include "chrome/browser/chromeos/gdata/gdata_errorcode.h"
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "base/file_path.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "base/platform_file.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/gdata/gdata_parser.h"
 #include "net/base/io_buffer.h"
 #include "googleurl/src/gurl.h"
 
 namespace gdata {
 
+class GDataEntry;
+
 // Struct for response to ResumeUpload.
 struct ResumeUploadResponse {
   ResumeUploadResponse(GDataErrorCode code,
                        int64 start_range_received,
                        int64 end_range_received);
   ~ResumeUploadResponse();
 
   GDataErrorCode code;
   int64 start_range_received;
   int64 end_range_received;
@@ skipping 69 matching lines @@
 
 // Callback type for DocumentServiceInterface::InitiateUpload.
 typedef base::Callback<void(GDataErrorCode error,
                             const GURL& upload_url)> InitiateUploadCallback;
 
 // Callback type for DocumentServiceInterface::ResumeUpload.
 typedef base::Callback<void(
     const ResumeUploadResponse& response,
     scoped_ptr<gdata::DocumentEntry> new_entry)> ResumeUploadCallback;
 
+// Callback type used to get result of file search.
+// If |error| is not PLATFORM_FILE_OK, |entry| is set to NULL.
+typedef base::Callback<void(base::PlatformFileError error, GDataEntry* entry)>
+    FindEntryCallback;
+
 }  // namespace gdata
 
 #endif  // CHROME_BROWSER_CHROMEOS_GDATA_GDATA_PARAMS_H_