Get AboutResource as account metadata for Drive V2.

chrome/browser/chromeos/gdata/gdata.proto

 // 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.
 //
 // Protocol buffer definitions for serializing GData files and directories.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
@@ skipping 64 matching lines @@
 message GDataDirectoryProto {
   optional GDataEntryProto gdata_entry = 1;
   repeated GDataDirectoryProto child_directories = 7;
   repeated GDataEntryProto child_files = 9;
 }
 
 // Container for the root directory and the largest changestamp.
 // TODO(satorux): Remove this: crbug.com/137862
 message GDataRootDirectoryProto {
   optional GDataDirectoryProto gdata_directory = 1;
-  optional int32 largest_changestamp = 2;
+  optional int64 largest_changestamp = 4;
   // Monotonically increasing version number, which is changed when
   // incompatible change is made in the proto file.
   // kProtoVersion in gdata_files.h defines the current version.
   optional int32 version = 3;
 }
 
 // Message to store information of an existing cache file.
 // Cache files are stored in 'tmp' or 'persistent' directory under the
 // root cache directory. See GDataCache::GetCacheRootPath().
 message GDataCacheEntry {
@@ skipping 11 matching lines @@
 
   // True if the file is a mounted archive file.
   optional bool is_mounted = 5;
 
   // True if the file is in the persistent directory.
   optional bool is_persistent = 6;
 
   // When adding a new state, be sure to update TestGDataCacheState and test
   // functions defined in gdata_test_util.cc.
 }