Add luma capabilities to ColorStateList

It's now possible to define an lStar attribute.
This attribute will modify the base color in a way that its chroma will
be conserved, but perceptive luminance will change.

Fixes: 183609373
Test: atest ColorStateListTest
Change-Id: I341a0a532bd9c030e8f52185bacda0db55486216
4 files changed