Make sure that live tile overlay is added only once.

Users report seeing empty launcher. After adding some logging, live tile
overlay can be added twice and removed only once. I added some logic to
make sure that it can only be added once.

Test: manual
Fixes: 135864059
Change-Id: I9d3325c56e76654f1397cc65979b97a6c0a80aee
(cherry picked from commit d3ef57b4)