gdata: Fix a bug where |root_| was accessed without a lock

chrome/browser/chromeos/gdata/gdata_file_system.h

Index: chrome/browser/chromeos/gdata/gdata_file_system.h
diff --git a/chrome/browser/chromeos/gdata/gdata_file_system.h b/chrome/browser/chromeos/gdata/gdata_file_system.h
index 1d5eb27eec4515f0e036ccaad8620784a461d502..8a001fc1b39b3a7b658d65a8e467a31fae581627 100644
--- a/chrome/browser/chromeos/gdata/gdata_file_system.h
+++ b/chrome/browser/chromeos/gdata/gdata_file_system.h
@@ -1214,10 +1214,9 @@ class GDataFileSystem : public GDataFileSystemInterface,
     const base::Closure& request_task,
     const base::Closure& reply_task);
 
-  // Helper function used to perform file search on the calling thread of
-  // FindEntryByPath() request.
-  void FindEntryByPathOnCallingThread(const FilePath& search_file_path,
-                                      const FindEntryCallback& callback);
+  // Helper function used to perform synchronous file search on UI thread.
+  void FindEntryByPathSyncOnUIThread(const FilePath& search_file_path,
+                                     const FindEntryCallback& callback);
 
   void OnSetPinStateCompleted(const FileOperationCallback& callback,
                               base::PlatformFileError error,