We're going to need this in order to fix <rdar://problem/35205373>, in Mail compose.
Created attachment 370622 [details] Patch
Comment on attachment 370622 [details] Patch Thanks for the review!
Comment on attachment 370622 [details] Patch Clearing flags on attachment: 370622 Committed r245775: <https://trac.webkit.org/changeset/245775>
All reviewed patches have been landed. Closing bug.