Segfault when calling JSON.stringify() on HTMLCollection

[0b10011]

Steps to reproduce

1. Set content of /src/test/html/content/test_prototype.js to:

   JSON.stringify(window.document.getElementsByTagName('script'));
   finish();
   

2. Run ./servo ../src/test/html/content/test_prototypes.html in terminal

3. Results in a Segfault

[evilpie]

The servo DOM bindings are missing an implementation of getOwnPropertyNames.

[jdm]

Where does JSON.stringify come into the example?

[0b10011]

@jdm Oops, typed the test case in manually to get it formatted correctly, but typed it wrong. Updated test case. Sorry about that!

[jdm]

For future reference: servo/rust-mozjs#33

[jdm]

Closing in favour of #2215 which has more details on how to solve it.