My patch for bug 209275 needs to find the first <base> tag with an href during nsHTMLSharedElement::UnbindFromTree. Right now, it manually walks the DOM to find it. I'd like to use NS_GetContentList, but I can't, because that flushes content notifications, and when I call it from UnbindFromTree, I don't find the nodes I'm looking for. Once we land the HTML5 parser and get rid of content notifications, we should clean this code up.
Marking dependent on bug 483780 which depends on migrating the XML side to use the nsHtml5TreeOpExecutor mechanism.