function showSeekedOverlay(player, duration, isForward) {
  const overlayJsx = (
    <div>
      <p>
        {isForward ? '+' : '-'}
        {duration}
      </p>
    </div>
  );

  showOneOffOverlay(player, OVERLAY_CLASS_SEEKED, overlayJsx, 'center');
}
Displays a transient "Seeked" overlay.

@param player The videojs instance.
@param duration The seek delta duration.
@param isForward true if seeking forward, false otherwise.