Add an option to specify requested fields for fetching metadata.

chrome/browser/sync_file_system/local/syncable_file_system_operation.cc

 // Copyright 2013 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.
 
 #include "chrome/browser/sync_file_system/local/syncable_file_system_operation.h"
 
 #include "base/logging.h"
 #include "chrome/browser/sync_file_system/local/local_file_sync_context.h"
 #include "chrome/browser/sync_file_system/local/sync_file_system_backend.h"
 #include "chrome/browser/sync_file_system/local/syncable_file_operation_runner.h"
@@ skipping 158 matching lines @@
 
 void SyncableFileSystemOperation::FileExists(
     const FileSystemURL& url,
     const StatusCallback& callback) {
   DCHECK(CalledOnValidThread());
   impl_->FileExists(url, callback);
 }
 
 void SyncableFileSystemOperation::GetMetadata(
     const FileSystemURL& url,
+    int fields,
     const GetMetadataCallback& callback) {
   DCHECK(CalledOnValidThread());
-  impl_->GetMetadata(url, callback);
+  impl_->GetMetadata(url, fields, callback);
 }
 
 void SyncableFileSystemOperation::ReadDirectory(
     const FileSystemURL& url,
     const ReadDirectoryCallback& callback) {
   DCHECK(CalledOnValidThread());
   // This is a read operation and there'd be no hard to let it go even if
   // directory operation is disabled. (And we should allow this if it's made
   // on the root directory)
   impl_->ReadDirectory(url, callback);
@@ skipping 195 matching lines @@
     operation_runner_->OnOperationCompleted(target_paths_);
   callback.Run(result, bytes, complete);
 }
 
 void SyncableFileSystemOperation::OnCancelled() {
   DCHECK(!completion_callback_.is_null());
   completion_callback_.Run(base::File::FILE_ERROR_ABORT);
 }
 
 }  // namespace sync_file_system