Add depth to -1 screen

Wallpaper will zoom out as you drag the overlay

Test: manually pull overlay
Fixes: 192502999
Change-Id: I9067b70d10497d4e16a5ef601161fbedfa9307e1
Merged-In: I9067b70d10497d4e16a5ef601161fbedfa9307e1
(cherry picked from commit 87d752062e9df6fffa7beb907b899cac69359f11)
3 files changed