Missing itemReviewed property for AggregateRating

[nokimaro]

AggregateRating should contain itemReviewed property.
https://schema.org/AggregateRating

Not sure, but it looks like property was removed at release >= 0.0.11

<script type="application/ld+json">{"@context":"http:\/\/schema.org","@type":"AggregateRating","sameAs":"https:\/\/example.com/item","reviewCount":"129","ratingValue":"3.40","bestRating":5,"worstRating":1,"ratingCount":"129"}</script>

This is example context generated with current property-set for AggregateRating
You can check it at Google Schema Validator https://search.google.com/structured-data/testing-tool
Check result: 1 error - The review has no reviewed item specified.

[nokimaro]

itemReviewed property was removed by mistake or on purpose?

[usmr]

<script type="application/ld+json">
{
	"@context": "http://schema.org/",
	"@type": "AggregateRating",
	"itemReviewed": "Example Item",
	"reviewCount": "10",
	"ratingValue": "4.5"
}
</script>