[#33962] Use a proxy function to close modals.

Because otherwise, we will always be stuck with SqueezeBox/Mootools.

Tracker: http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=33962&start=0
@okonomiyaki3000 It seems to be a copy-paste result. You are right it can be changed to
```js
window.location="index.php?option=com_menus&view=item&task=item.setType&layout=edit&type=" + type;
```
When is this file called from a non-tmpl view?