Keyguard: Fix missing IME, and apply better animations

Password bouncer: animate the text field alpha and y positioning along
with the IME reveal. Also fix the ordering of focus events to ensure
the soft keyboard appears.

Fixes: 174020436
Fixes: 175243820
Test: SystemUITests
Change-Id: I62898870f57da1cd5b3da6bc4a2cfb23fe95097f