In `wp_audio|video_shortcode()`, make sure that `autoplay` and `loop` are booleans. Passing `'false'` to them will force them to be active, which is bad. 

Fixes #29825.


git-svn-id: https://develop.svn.wordpress.org/trunk@30185 602fd350-edb4-49c9-b593-d223f7449a82