going directly to backup after face unlock fails 15 times

- after 15 failed face unlock attempts, go to backup until the backup method is successful
- if the backup method times out (because too many unsuccessful unlocking attempts),
  face unlock will not be launched until the backup method is used sucessfully
- fixes 5365919

Change-Id: I9aef7a4f1abcceefc5d6f1c0458ae5cbe8a902df