gdata: Reduce use of GetWeakPtrForCurrentThread()

chrome/browser/chromeos/gdata/gdata_file_system.cc

Index: chrome/browser/chromeos/gdata/gdata_file_system.cc
diff --git a/chrome/browser/chromeos/gdata/gdata_file_system.cc b/chrome/browser/chromeos/gdata/gdata_file_system.cc
index 18eae5de1d87487ce19e7264c9841371d9dcfcc0..60a99723b544f65dad59cec033e2c6c43a961430 100644
--- a/chrome/browser/chromeos/gdata/gdata_file_system.cc
+++ b/chrome/browser/chromeos/gdata/gdata_file_system.cc
@@ -1137,7 +1137,7 @@ void GDataFileSystem::TransferFile(const FilePath& local_file_path,
                  local_file_path,
                  resource_id),
       base::Bind(&GDataFileSystem::TransferFileForResourceId,
-                 GetWeakPtrForCurrentThread(),
+                 ui_weak_ptr_,
                  local_file_path,
                  remote_dest_file_path,
                  callback,
@@ -1187,7 +1187,7 @@ void GDataFileSystem::TransferRegularFile(
                  error,
                  upload_file_info),
       base::Bind(&GDataFileSystem::StartFileUploadOnUIThread,
-                 GetWeakPtrForCurrentThread(),
+                 ui_weak_ptr_,
                  callback,
                  error,
                  upload_file_info));
@@ -1236,7 +1236,7 @@ void GDataFileSystem::StartFileUploadOnUIThread(
 
   upload_file_info->completion_callback =
       base::Bind(&GDataFileSystem::OnTransferCompleted,
-                 GetWeakPtrForCurrentThread(),
+                 ui_weak_ptr_,
                  callback);
 
   service->uploader()->UploadFile(scoped_ptr<UploadFileInfo>(upload_file_info));