hasOwnProperty in _grid function in wax.mm.interaction

[svanderbleek]

when using for in with libraries that modify Object.prototype this causes erroneous keys to be attempted, note that there are other places in the code with similar for in statements that may produce errors as well

[tmcw]

Thanks! Luckily such libraries are becoming less common, and those that do that kind of evil stuff use defineProperty and to make the new props non-enumerable. But always good to be careful.