Revert "Fix potential deadlock between LockScreen and WindowManagerService"

This reverts commit aca25241b10dc4a794eec9e3a80ad30d2c76f2ce.
Revert "Fix divisions by zero on boot."

This reverts commit 93a3d8477ae819896421108625fb799fc2f42c67.
Revert "SystemUI: fix memory leaks"

This reverts commit 447875cb88ebe7dec2152504b2729287186c998c.