[css-regions] Invalid access in NamedFlowCollection

Hi all,
Currently the spec says that should a script try to retrieve an inexistent object from a NamedFlowCollection, either by using an out-of-range index or an invalid name, it should return *null*.
I think it would be better to return *undefined* instead, for a couple of reasons:

*         Currently all JavaScript and HTMLCollection-s return *undefined* for invalid keys (e.g. Array, document.forms, document.querySelectorAll() )

*         Also, in general, null doesn't mean that there's nothing there, but actually that something might be there, but it's not a definite object (yet)

Anyone has any thoughts on this?

Thanks,
m.

Mihai Balan | Quality Engineer / WebKit team |  mibalan@adobe.com<mailto:mibalan@adobe.com> | +4-031.413.3653 / x83653 | Adobe Systems Romania