Adopt the new NodeName enumeration more broadly in attributeChanged() overrides.
Pull request: https://github.com/WebKit/WebKit/pull/12754
Committed 262999@main (0b09da912f83): <https://commits.webkit.org/262999@main> Reviewed commits have been landed. Closing PR #12754 and removing active labels.
<rdar://problem/108079389>