Also update color when changing the visibility

We were updating the text field color only during some code paths,
which is error prone and doesn't handle visibility events well.

Also, the color of the field on AOD should never be red, according to UX
guidance.

Fixes: 149891226
Test: manual
Test: atest KeyguardIndicationControllerTest
Change-Id: I6e244786e72d90f00b0b733bdcb00c3e8e03582f