Creating the CSSParserContext is slightly expensive, since it fetches all of the relevant document Settings.
<rdar://problem/112741540>
rdar://112439220
Pull request: https://github.com/WebKit/WebKit/pull/16025
Committed 266238@main (5ec234192a2e): <https://commits.webkit.org/266238@main> Reviewed commits have been landed. Closing PR #16025 and removing active labels.