Add content color scheme for media

Use content color scheme for media player, which dynamically adapts
color palette chromas to the source color, and permits monochrome source
colors. Use for media. This allows ex. grayscale album covers to get a
grayscale treatment in UI, per design requirement.

Bug: 213314628
Test: Manual inspection at runtime
Change-Id: Ib8ea007e34758cd7903b3432ab88af695cb22f68
4 files changed