Fixes: 184965821
Test: On various devices:
adb shell settings put secure biometric_app_enabled 0/1
adb shell settings put secure biometric_keyguard_enabled 0/1
Test: On face-only devices that shipped before S:
Existing settings (settings > security > face unlock) are not
affected and still work.
Newly added secure settings do not take effect (as expected)
Test: atest com.android.server.biometrics
Test: atest KeyguardUpdateMonitorTest
Change-Id: Ie0fda46facefd3ecfbbce6ef769d6d8e9fdfb09b
875b80655c