content-visibility: add compat features (#280)

Co-authored-by: François Daoust <[email protected]>

Author: ddbeck

feature-group-definitions/content-visibility.yml

@@ -1,2 +1,7 @@
 spec: https://drafts.csswg.org/css-contain-2/#content-visibility
 caniuse: css-content-visibility
+compat_features:
+  - api.ContentVisibilityAutoStateChangeEvent.ContentVisibilityAutoStateChangeEvent
+  - api.ContentVisibilityAutoStateChangeEvent.ContentVisibilityAutoStateChangeEvent.skipped
+  - api.ContentVisibilityAutoStateChangeEvent
+  - css.properties.content-visibility