code: public void updateSpan(MentionSpan span) {
          mBlockCompletion = true;
          Editable text = getText();
          int start = text.getSpanStart(span);
          int end = text.getSpanEnd(span);
          if (start >= 0 && end > start && end <= text.length()) {
              text.removeSpan(span);
              text.setSpan(span, start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
          }
          mBlockCompletion = false;
      }
docs: Resets the given {@link MentionSpan} in the editor, forcing it to redraw with its latest drawable state.
  
  @param span the {@link MentionSpan} to update