[giow] (3) <input type=hidden> doesn't ever render
Fixing https://www.w3.org/Bugs/Public/show_bug.cgi?id=19648
Affected topics: Rendering

git-svn-id: http://svn.whatwg.org/webapps@7765 340c8d12-0b0e-0410-8428-c7bf67bfef74