Revert^2 "[Media] Update background gradient scrim to use album theme colors."

This reverts commit a95afa554cab13c1d32ad2df0e005fb6defc1f54.

Reason for revert: Updated the original CL to fix failing MediaControlPanelTest.

Change-Id: I41654ad490c8e4946e59fafbe4a48dc2cd332d97
7 files changed