AFAIK, pretty much none of the driverless systems are using parallax. The reason why not is that parallax only gives good depth information at most up to about 10 feet. Disparity mapping is pretty limited in real life.
Instead they get depth from video.
I'd imagine in almost every situation the car would cast a shadow to that featureless wall. Although Tesla might not have a camera placed to a right spot to actually see that shadow...