Fix Volume panel background [Dark UI]

Volume panel is a bit out of the box compared to the normal theming.
Reapply the background via java code on theme change.

Change-Id: I0df41a95487f7c23d5fda5c2ec7df763c8e2f466
what?

Change-Id: If3ee04b1b941e25e9f844a038974e61ca49b530e