Precomputed AO Mask is no longer working

Precomputed AO Mask is no longer working in 4.11 Preview 1. This is a Regression from 4.10.x where this was working as intended.

I've attached a zip file with the quick test that can be dropped into the content folder. Content was made with 4.10.

1. Open UE4
2. Enable Precomputed AO Mask in the World Settings
3. Setup a material to use the Mask (**Material setup from Documentation)
4. Build for the level

Results: Mask currently does not work when enabled.

Expected: Mask will work when enabled

Regression: Yes