Bug 142738 added support for WPT submodules description. But it does not care of submodules of submodules which happens to be used in WPT now.
Created attachment 272016 [details] Patch
Comment on attachment 272016 [details] Patch Clearing flags on attachment: 272016 Committed r197027: <http://trac.webkit.org/changeset/197027>
All reviewed patches have been landed. Closing bug.