Cancel UDFPS enrollment on overlay focus loss

Integrate onWindowFocusChanged() to FingerprintEnrollEnrolling
When the activity window lost focus, we just cancel this enroll
session, and create a dialog to notify user.

* Keep legacy rotation behavior, do not cancel enrollment if user
  rotate device.
* This change will cancel enrollment when user interrupted by
  1) Swipe down Notification Shade
  2) Heads up notification expand
  3) Bubble Expanded
  4) Google Assist
  5) PIP expand
  6) Recents
  7) Launch Power Menu(Global Action)

Test: manual test above scenario
Test: m RunSettingsRoboTests -j30 ROBOTEST_FILTER=FingerprintEnrollEnrollingTest
Bug: 228261883
Bug: 242478941
Bug: 227905887
Change-Id: Id097e6b15928646cd5ab91c2a1f6eb1bb9bf190b