Properly launch activities that show over lock

We need to check if the activity can show over the lockscreen in order
to decide which path to use. If true, we do something similar as
Notifications.

Test: manual, using test app
Test: atest ActivityStarterImplTest
Test: atest CtsTileServiceTestCases CtsSystemUiHostTestCases
Fixes: 292112939

Change-Id: I30caf9d6b3ab1f5fc567c87a3f0a5f67f512da3b