[Chipbar] Fix the color of the start icon to match the new theme.

Fixes: 273969888
Bug: 267821684

Test: active unlock chipbar watch icon has correct tint in light and
dark mode
Test: media ttt chipbar with default icon and app icon has correct tint
in light and dark mode
Test: media ttt receiver default icon has correct tint in light and dark
mode
Test: atest MediaTttUtilsTest MediaTttChipControllerReceiverTest
ChipbarCoordinatorTest

Change-Id: I992d9f1654ee3592a3ffd7c5aa50f00af5194752