Pane for 'page title' doesn't always render a title

It looks like the content pane for Page title incorrectly returns if there is no value retrieved for drupal_get_title(). According to these issues Panels won't actually set the page title this way if it's set through the Panels UI, so checking it this way often returns nothing when there really is a page title set.

Removing the following code allows my title to display correctly on the page:

  if (!drupal_get_title()) {
    return;
  }

Patch attached for review.