It's been more than 2 years when WebKit updated html5lib test data in bug 74343, and it looks like there are some minor improvements in html5lib since then.
Created attachment 229228 [details] Patch
Comment on attachment 229228 [details] Patch ah, wait, canceling the r?. Turned out that some tests were added by webkit team on top of html5lib, and should not be deleted. I'll merge them, rather than overwriting.
Created attachment 229234 [details] Patch
Comment on attachment 229234 [details] Patch Clearing flags on attachment: 229234 Committed r167213: <http://trac.webkit.org/changeset/167213>
All reviewed patches have been landed. Closing bug.