Fix regression of pressing power key cancel sfps enrollment

Previous ag/19699461 used to fix UdfpsControllerOverlay bug.
However, we didn't consider a feature click power button to
notify user with a Toast on sfps project.

Bug: 245383975
Bug: 228261883
Bug: 242478941
Bug: 227905887
Test: make RunSettingsRoboTests ROBOTEST_FILTER=FingerprintEnrollEnrollingTest
Test: manual verify sfps enrollment, press/long press power key would
not cancel enrollment.
Test: manual verify udfps enrollment, UdfpsControllerOverlay lose focus
cancel enrollment.

Change-Id: I44394bdb91660b27a704064a7f7cdc5d0ad95d30