Collect+write test pages for JavaScript hooks
Looks like Firefox changed some aspects of its JS scope resolution: https://bugzilla.mozilla.org/show_bug.cgi?id=632064
We should review that. Along the way, I should also collect the set of circumvention tests from Greg Fleischer as well as gather my own tests, and try to distill them down into a couple simple web pages.
I should also verify WebWorker scope and other newer JS tech still gets the hooks properly applied to it.