First I'm going to make the test editing/mac/spelling/editing-word-with-marker-1.html work on iOS. That change is significant enough that I want to do it in its own patch. Once done, we can move the test to editing/spelling/.
Created attachment 399622 [details] Patch
Thanks Simon!
Created attachment 399784 [details] To Land
Committed r261896: <https://trac.webkit.org/changeset/261896>
<rdar://problem/63422095>