Revert "Revert "Ensure SystemUI gets restarted lazily.""

This reverts commit d4c3da1be348b14b355df23c156f4a5d47262fff.

Reason for revert: Need to restore this functionality. Problem fixed.

Bug: 257302229
Test: manual via the flag app
Change-Id: Ieefc76bda09431ed2f7a0fe28d91a59ef02184b8
8 files changed