MediaPlayer will now transition the background with color scheme

This change transitions the media player background whenever
the related color scheme has changed. Since the color scheme
is usually generated from the background, it should not trigger
superflous transitions.

Fixes: 246956968
Test: atest MediaControlPanelTest ColorSchemeTransitionTest
Change-Id: I963afcf4ba0fd8c2e9ebca4d634098f63454fab6
Merged-In: I963afcf4ba0fd8c2e9ebca4d634098f63454fab6
3 files changed