Create two courses, both with guest access set to Yes. For the second course, set a key. View the category list (course/index.php?categoryid=x) You should see that both courses have a guest access icon which looks in the standard theme like a person's head. The second course with the key set should include a small key in the icon. Hover over both icons (or inspect in firebug). Note that both have the same alt and title text "Guest Access". Apply the patch, then look at the alt and title text for both icons again. The course with the key should now have different alt & title text indicating that a key is required.