[JSC] Fix Object.assign fast path to accept undefined/null
Created attachment 433071 [details] Patch
<rdar://problem/80264271>
Comment on attachment 433071 [details] Patch LGTM too.
Committed r279690 (239495@main): <https://commits.webkit.org/239495@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 433071 [details].