Fix settings crash due to enrolling error

Test: There's a condition where FP enrollment fails and a fragment
transaction/commit occurs after onSaveInstanceState. We should be
using commitAllowingStateLoss() instead of commit()

I'm not able to repro this issue but from looking at the stack
trace this should fix the problem.


Fixes: 38432354

Change-Id: I56b9c8d2efc45e9d77f29b897280f5378c3a84a0