in preparation for the MQ4 parser.
<rdar://problem/100889255>
Created attachment 462863 [details] Patch
Created attachment 462866 [details] Patch for landing
Committed 255278@main (4476aad722d2): <https://commits.webkit.org/255278@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 462866 [details].