Added a new API to colorize notifications

Ongoing notifications can now be colorized.
This will use the color provided as the background
and invert most text colors

Test: runtest -x cts/tests/app/src/android/app/cts/NotificationTest.java
Bug: 34469375
Change-Id: I818e8db96c868d8bcde8f28c253efd581eeccaa2