Fixed initial user on UserVisibilityMediator.

Otherwise, the system user never finishes booting as when
WindowManager calls isUserVisible(0), it will return false.

Fixes: 258696493
Test: it boots!
Test: atest UserVisibilityMediatorSUSDTest atest UserVisibilityMediatorMUMDTest

Change-Id: I316e1469977e7a04389d7e0cfab0ff88d3b42481
1 file changed