Found e.g. in Phoca Download 3.0.5 site/views/play/tmpl/default.php(14) - but there are much more.

Also you should remove the assignments in (admin) controller.php(53) where parent::display() is called. In line 52 on function definition it's ok as default param, but not in a function call. (same found in Phoca Maps 3.0.1).
Best regards,
Hoffi