Add https://html.spec.whatwg.org/multipage/scripting.html#dom-customelementregistry-get which returns the constructor of a custom element.
Created attachment 287476 [details] Adds the support
Created attachment 287477 [details] Adds the support
Comment on attachment 287477 [details] Adds the support r=me
Comment on attachment 287477 [details] Adds the support Clearing flags on attachment: 287477 Committed r205220: <http://trac.webkit.org/changeset/205220>
All reviewed patches have been landed. Closing bug.
<rdar://problem/28090963>