This improves type safety, gives the optimizer more information to work with, and generally makes more sense (an AXIsolatedObject should never be able to return the other AXCoreObject variant, AccessibilityObject.
<rdar://problem/116507428>
Created attachment 468071 [details] Patch
Committed 268922@main (aff9d67b9c8f): <https://commits.webkit.org/268922@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 468071 [details].