Avoid unnecessary call to toJS() in willCreatePossiblyOrphanedTreeByRemovalSlowCase().
Pull request: https://github.com/WebKit/WebKit/pull/11635
Committed 261800@main (e7acfe5b0dbf): <https://commits.webkit.org/261800@main> Reviewed commits have been landed. Closing PR #11635 and removing active labels.
<rdar://problem/106867804>