Updated bubble bar expanded bubble menu appearance

Set the appropriate colors for the expanded bubble menu views.

Fixes: 356944031
Flag: com.android.wm.shell.enable_bubble_bar
Test: manual. Light theme screenshot:
https://screenshot.googleplex.com/4F7wGUpPLfGe8V6
dark theme screenshot:
https://screenshot.googleplex.com/Bqp9G7kWjYUfCri

Change-Id: I3664d1b4b2f1a45c35a2bd3d3e6e9d8c87dfdf78