Stopping Face Unlock immediately on detaching from window fixes 7338808

The refactoring broke my fix for 7222226.  We need to stop Face Unlock without
any messaging delay when the window is detached to avoid it starting with an
invalid window, or stopping right after it restarts.

Change-Id: Iea23989ec2ab3ad7d1a57e2d1fb85163a6396024
1 file changed