Enabled the accessibility isolated tree for the right platforms and add it as a runtime xperimental feature
<rdar://problem/58131075>
Created attachment 386306 [details] patch
Created attachment 386368 [details] patch
Created attachment 386376 [details] Patch
Created attachment 386377 [details] patch
Created attachment 386378 [details] patch
Created attachment 386379 [details] patch
Created attachment 386381 [details] patch
Created attachment 386383 [details] patch
The commit-queue encountered the following flaky tests while processing attachment 386383 [details]: transitions/default-timing-function.html bug 138901 (authors: dino@apple.com and graouts@apple.com) The commit-queue is continuing to process your patch.
Comment on attachment 386383 [details] patch Clearing flags on attachment: 386383 Committed r254115: <https://trac.webkit.org/changeset/254115>
All reviewed patches have been landed. Closing bug.
This has broken internal testing.
(In reply to Truitt Savell from comment #13) > This has broken internal testing. can you email me the details