Make foreground color selection in SmartReplyView and RemoteInputView match Notification.

Fixes: 196585371
Test: post colorized notification with luminance between .2 and .5; validate that smart replies and remote input use black text to match the notification.
Change-Id: I5ea69181755ed5c2b48352a0379ae4e898202e21
Merged-In: I5ea69181755ed5c2b48352a0379ae4e898202e21