Reland "Default undefined PRODUCT_SHIPPING_API_LEVEL to fake treble"

This is a temporary measure to disable treble sepolicy tests for
non-compliant targets.

Bug: 113124961
Bug: 111243627
Change-Id: I83d6efad0ff5c7d87a4b990560c390b66aeb3653
Test: m selinux_policy
1 file changed