Revert "Revert "Show "Add users from lock screen" dependent on secure lock screen.""

And fix the failing test that caused the revert.

Bug: 148015798
Bug: 149209670
Test: make -j64 RunSettingsRoboTests

This reverts commit 666dacc32aafd2ee5dea5564367598855825eed8.

Change-Id: I34bb82e621e009ec26c28835f309e7a5b996e9b3
3 files changed