Don't dismiss keyguard if guest has Pin/Pattern/PW set

Fixes: 38140390

Test: 1) create a guest, make sure if no pw is set keyguard dismisses
2) set a pw for the guest, make sure keyguard doesn't dismiss
3) lockout fingerprint by failing fp 5 times, then switch back to guest.
make sure error message is on bottom of screen.

Change-Id: Ic66fb3ac3e9bb62ac068f36208c73ffc14fe78d5