We can merge the contents of appendChild into cloneNodeInternal.
Pull request: https://github.com/WebKit/WebKit/pull/16121
Pull request: https://github.com/WebKit/WebKit/pull/16144
Committed 266373@main (af3763363c5b): <https://commits.webkit.org/266373@main> Reviewed commits have been landed. Closing PR #16144 and removing active labels.
<rdar://problem/113007930>