Send media view holder inflation to background

This CL handles the issues happened in b/271967119 when we tried to send
inflations to background thread.
It also makes sure that onMeasure get the right measurements in case
media view controllers are not yet in added.

Flag: com.android.systemui.media_controls_umo_inflation_in_background
Fixes: 368514198
Test: atest MediaCarouselControllerTest
Change-Id: I5f2974493ae9a6c46fd792ba9bdca856bc75d42a