Add support for custom annotations in the CSS BNF syntax to allow us to pass information about particular nodes directly from the JSON.
<rdar://problem/103817055>
Pull request: https://github.com/WebKit/WebKit/pull/8136
Committed 258410@main (78551d0c1acb): <https://commits.webkit.org/258410@main> Reviewed commits have been landed. Closing PR #8136 and removing active labels.