[SB][Screen Chips] Allow different chips to have different colors.

This sets the call chip to have a "themed" look (its coloring matches
whatever theme color is set) and sets all the screen sharing chips to
have a "red" look (always dark red background with white text).

Bug: 332662551
Flag: com.android.systemui.status_bar_screen_sharing_chips

Test: Cast-to-other-device chip, share-to-app chip, and screen recording
chip all have red coloring. Change between light & dark mode and verify
chip always stays same color. Change theme color and verify chip always
stays same color.
Test: Call chip has themed coloring
Test: Start a call, then change theme colors -> verify call chip updates
to new color

Test: Start a call, then start screen recording -> verify chip coloring
changes
Test: Then, change theme colors. Then, end the screen recording ->
verify call chip reappears in the new theme colors

Change-Id: I43ca05c48a9fdcaf3f00b4c62e7d0fc10a43c3f2