See http://wpt.live/css/css-fonts/parsing/font-computed.html Some longhands should be omitted from the shorthand serialization when set to `normal`.
<rdar://problem/101468196>
Pull request: https://github.com/WebKit/WebKit/pull/5688
Committed 255905@main (df1cf06ce2e2): <https://commits.webkit.org/255905@main> Reviewed commits have been landed. Closing PR #5688 and removing active labels.