Fix for navbar back/home appearing in keyguard (multiuser).

Clear remembered sysui visibility flags in PhoneWindowManager
when switching users. They might have been from another user.

Then reapply current window's flags to ensure contribution
makes it to the status bar.

Bug:7506446
Change-Id: I8249ba006934bdc22b952da7c16e9983d091c489
1 file changed