public synchronized MultiMap<String, VirtualFile> getBranchToFileMap() {
    final MultiMap<String, VirtualFile> result = new MultiMap<>();
    for (final VirtualFile vf : myMap.keySet()) {
      result.putValue(myMap.get(vf).getSecond(), vf);
    }
    return result;
  }
public synchronized MultiMap<String, VirtualFile> getBranchToFileMap()