General Fallback for BiometricPrompt

Previously, we nuanced the fallback around the DEVICE_CREDENTIALS bit,
and allowed other cases to propagate.

Now, we generalize the scope of the initial fallback to avoid having to
call the biometric API at all (and thus avoid the onError() response for
a vast majority of the use cases).

Bug: 334197980
Test: Video tests in the bug and build test
Change-Id: Iee78237156c15400ef5a293ad86b38a43b128e9e
1 file changed