If I try copying and pasting the encoded source into Chrome's JS console, it gives the following error:

    TypeError: Array.prototype.sort called on null or undefined.

I would be interested to see what exactly it's doing, and how alert("Hello World"); gets mangled to call Array.prototype.sort().

EDIT: I should note that I get this error no matter what code I put in. I think Chrome's Javascript interpreter is somehow interpreting some of that boilerplate as a call to Array.prototype.sort() somehow.