If the media player disappears, request a relayout

This happens because the total size of QS doesn't change, but
NPV needs to be notified that it needs to relayout notifications based
on a new height of QQS.

Test: manual
Fixes: 385810029
Flag: com.android.systemui.qs_ui_refactor_compose_fragment
Change-Id: I5ac37b41d7ec949fd24c79ddab59d0a1db47b036