Rename AbstractFrameView to FrameView, now that FrameView was renamed to LocalFrameView.
Pull request: https://github.com/WebKit/WebKit/pull/11557
Committed 261701@main (c97ae74f40fd): <https://commits.webkit.org/261701@main> Reviewed commits have been landed. Closing PR #11557 and removing active labels.
<rdar://problem/106766343>