Most subcomponents are there already.
Created attachment 383741 [details] patch
Created attachment 383743 [details] patch
Created attachment 383746 [details] patch
Comment on attachment 383746 [details] patch Clearing flags on attachment: 383746 Committed r252546: <https://trac.webkit.org/changeset/252546>
All reviewed patches have been landed. Closing bug.
<rdar://problem/57286344>