Import web-platform-tests/uievents tests from usptream.
Created attachment 414509 [details] Patch
Comment on attachment 414509 [details] Patch rs=me
Created attachment 414586 [details] Patch
Committed r270037: <https://trac.webkit.org/changeset/270037> All reviewed patches have been landed. Closing bug and clearing flags on attachment 414586 [details].
<rdar://problem/71590032>
Follow-up for iOS in https://trac.webkit.org/changeset/270050.