gdata: Make GDataFileSystem::ReadDirectoryByPath() much more efficient

chrome/browser/chromeos/gdata/gdata_download_observer.cc

 // 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.
 
 #include "chrome/browser/chromeos/gdata/gdata_download_observer.h"
 
 #include "base/callback.h"
 #include "base/file_util.h"
 #include "chrome/browser/chromeos/gdata/gdata.pb.h"
 #include "chrome/browser/chromeos/gdata/gdata_documents_service.h"
@@ skipping 455 matching lines @@
   upload_file_info->all_bytes_present = download->AllDataSaved();
 
   upload_file_info->completion_callback =
       base::Bind(&GDataDownloadObserver::OnUploadComplete,
                  weak_ptr_factory_.GetWeakPtr(),
                  download->GetId());
 
   // Get the GDataDirectory proto for the upload directory, then extract the
   // initial upload URL in OnReadDirectoryByPath().
   const FilePath upload_dir = upload_file_info->gdata_path.DirName();
-  file_system_->ReadDirectoryByPath(
+  file_system_->GetEntryInfoByPath(
       upload_dir,
-      base::Bind(&GDataDownloadObserver::OnReadDirectoryByPath,
+      base::Bind(&GDataDownloadObserver::OnGetEntryInfoByPath,
                  weak_ptr_factory_.GetWeakPtr(),
                  download->GetId(),
                  base::Passed(&upload_file_info)));
 }
 
-void GDataDownloadObserver::OnReadDirectoryByPath(
+void GDataDownloadObserver::OnGetEntryInfoByPath(
     int32 download_id,
     scoped_ptr<UploadFileInfo> upload_file_info,
     GDataFileError error,
-    bool /* hide_hosted_documents */,
-    scoped_ptr<GDataDirectoryProto> dir_proto) {
+    scoped_ptr<GDataEntryProto> entry_proto) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(upload_file_info.get());
 
   // TODO(hshi): if the upload directory is no longer valid, use the root
   // directory instead.
   upload_file_info->initial_upload_location =
-      dir_proto.get() ? GURL(dir_proto->gdata_entry().upload_url()) : GURL();
+      entry_proto.get() ? GURL(entry_proto->upload_url()) : GURL();
 
   StartUpload(download_id, upload_file_info.Pass());
 }
 
 void GDataDownloadObserver::StartUpload(
     int32 download_id,
     scoped_ptr<UploadFileInfo> upload_file_info) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(upload_file_info.get());
 
@@ skipping 64 matching lines @@
   // use the final target path when the download item is in COMPLETE state.
   file_system_->AddUploadedFile(UPLOAD_NEW_FILE,
                                 upload_data->virtual_dir_path(),
                                 entry.Pass(),
                                 download->GetTargetFilePath(),
                                 GDataCache::FILE_OPERATION_MOVE,
                                 base::Bind(&base::DoNothing));
 }
 
 }  // namespace gdata