Keyframes can set a custom property to "inherit". We should recompute keyframes if the value to which "inherit" would resolve changes during an animation. This is similar to work that we did in bug 251433.
Pull request: https://github.com/WebKit/WebKit/pull/9525
Submitted web-platform-tests pull request: https://github.com/web-platform-tests/wpt/pull/38344
Committed 259812@main (a2b572c83047): <https://commits.webkit.org/259812@main> Reviewed commits have been landed. Closing PR #9525 and removing active labels.
<rdar://problem/105003138>