[flexiglass] Failure animations for bouncer UIs.

- Adds a generic failure animation system to AuthMethodBouncerViewModel
  that all subclasses can easily use
- Introduces a use-case for it in PatternBouncerViewModel and a stub in
  PinBouncerViewModel for later implementation

Bug: 281871687
Test: Added unit tests for the failure animation UI state and logic in
AuthMethodBouncerViewModel, using PinBouncerViewModel as the underTest
instance because AuthMethodBouncerViewModel is a sealed class so it
cannot be extended, even for tests.
Test: manually/visually verified the staggered failuew animation in the
pattern bouncer UI. Please see b/281871687#comment4 for a video
recording.

Change-Id: I4d4d81e4d6e32943ae2fc715188e0f62dc28111d