It's the same camera/GPS mount as the Apple cars. This car did have a California license plate. It drove back, and by me again. This time I got a really good closeup burst in iPhone 6plus.
"Vehicle similar to the ones Apple is testing sighting in Florida."
I think even in the original "Apple car" stories, it mentions that the system on the top is leased from another company - so the camera/sensor apparatus on the top isn't Apple-specific; it's just that Apple seems to be the most prominent customer.