Specify order of attributes for parser-created elements

[ayg]

I think the desired behavior is that it's unspecified, because in practice implementations do not have a consistent order, and I recall past discussions were that some of them aren't willing to change. This should be specified explicitly, because it could be argued that the order should obviously match the DOM order unless specified otherwise. Alternatively, if implementations are willing to converge, we could specify that they match some specified order (e.g., DOM order).

[domenic]

This was discussed in WICG/webcomponents#474. #1012 causes the order to become specified, as we concluded there; Gecko will not be able to comply, but they are currently non-compliant in other ways related to attribute order.

[ayg]

Thanks! Good to know. If the change to the spec has already been agreed upon and will definitely happen soon, I'll close this now.