Fixed the layout of media heads up notifications

Previously the heads up layout was strangely clipped
because we were using the expanded layout.
We're now using the collapsed layout instead. In order to allow this,
the media notification needs to wrap it's height properly.

Fixes: 136507638
Test: show heads up media notification
Change-Id: Ib091b0e776b5cd1a615c9ea0121a3115817b7f64