If we pick both it will only work in opera, if we pick parentWindow
it will work in IE and Opera, if we pick defaultView it will work in
Firefox and Opera. So no matter which we pick it'll work better if we
just pick one.
If we pick both content will always be compliant... If we pick one and
it's not parentWindow it's not really usable in IE... If we pick
parentWindow specifications probably keep support for the other given
that it's already in another specification.
Like I said before, if there is a lot of content out there that uses
both then, I think we should add both. Is there?
/ Jonas
