Add useful details in attachment's save button's, including: Click location, modifier key statuses, and the coordinates of the save button inside the attachment (because the save button itself is in a shadow tree, and therefore not accessible by the client).
<rdar://problem/105952126>
Pull request: https://github.com/WebKit/WebKit/pull/10703
Committed 261101@main (b9dad072710a): <https://commits.webkit.org/261101@main> Reviewed commits have been landed. Closing PR #10703 and removing active labels.