[RONs] Colorize public version of RONs

We want RONs to stand out amoung other notifications on the lockscreen. Existing system does not support colorization for public contentview.
With this CL, we colorize them when they are RON.

Bug: 367705002
Flag: android.app.ui_rich_ongoing
Test: Enable "Don't show sensitive content on the lock screen", start screen recorder app, lock screen and check how this notification looks on the lock screen.
Change-Id: Iaf5dd44a09717395d693e2ad7f73db12b44dec1c