code: @Override
      protected void onFocusChanged(boolean focused, int direction,
                                    Rect previouslyFocusedRect) {
          super.onFocusChanged(focused, direction, previouslyFocusedRect);
          showErrorIconHax(lastErrorIcon);
      }
docs: In onFocusChanged() we also have to reshow the error icon as the Editor
  hides it. Because Editor is a hidden class we need to cache the last used
  icon and use that