Order of supported property names is not defined. See HTMLCollection in DOM
for how this probably should be done.
Posted from: 188.8.131.52 by firstname.lastname@example.org
User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_8_2) AppleWebKit/537.21 (KHTML, like Gecko) Chrome/25.0.1354.0 Safari/537.21
This is also true for HTMLOptionsCollection and to some extent true for HTMLPropertiesCollection (could use "tree order").
Checked in as WHATWG revision r7722.
Check-in comment: Try to define order for supported property names. This is not based on testing. If there are compatibility constraints here that prevent implementing this as specced, please let me know.