[Bouncer] Refine bouncer title.

Add animation to bouncer title. Also remove setMessageIfEmpty. Remove
instances of hiding the message in many cases as these cases were mean
to prevent the textview from flashing when bouncer isn't being shown.

Test: Tested simpin, simpuk, pattern, password, and pin on device. Also
added unit tests
Fixes: 174020764

Change-Id: I2f8e6f3d1a0400ead7e658b7d003dbc7b608a1cf