@@toStringTag spoofing for null and undefined

[Domenic Denicola]

From: Jordan Harband [mailto:ljharb at gmail.com] 

> Between the two issues I proposed, I definitely think that "something pretending to be a builtin" is far less hazardous then "altering builtins to appear to be something else".

I don't think that's a hazard, any more than the mutability of the many other things you can already override is a hazard.