public @Nullable FocusWatcher getFocusWatcherFor(Component c) {
    final Window window = SwingUtilities.getWindowAncestor(c);
    final WindowInfo info = window == null ? null : windowToInfo.get(window);
    return info == null ? null : info.myFocusWatcherRef.get();
  }
public @Nullable FocusWatcher getFocusWatcherFor(Component c)