These are only used internally, but not externally, so we should keep them in the ControlPart enum, but unexpose the CSS value.
<rdar://problem/93332035>
Created attachment 459409 [details] Patch
Pull Request: https://github.com/WebKit/WebKit/pull/632
Committed r294226 (250584@main): <https://commits.webkit.org/250584@main> Reviewed commits have been landed. Closing PR #632 and removing active labels.