Send user-activity to power manager on lock icon long press

To reset the screen timeout so the display won’t go to sleep
so quickly after a lock icon longpress.

Test: Manually swipe on lock icon, screen still timeouts,
but if a longpress is detected, the screen timeout resets
Fixes: 236930064

Change-Id: Idc799a3e2f06638401acd999d9cce1967f263d9b