<one-line summary, followed by blank line and full summary>

Test Plan:
Loaded
[this item](http://localhost:9000/test.html#content=%7B%22question%22%3A%7B%22content%22%3A%22%21%5B%5D%28https%3A%2F%2Fka-perseus-graphie.s3.amazonaws.com%2F3ab93765c75fa8d24a43400ba236fc7523fa6b5b.png%29%22%2C%22images%22%3A%7B%22https%3A%2F%2Fka-perseus-graphie.s3.amazonaws.com%2F3ab93765c75fa8d24a43400ba236fc7523fa6b5b.png%22%3A%7B%22width%22%3A425%2C%22height%22%3A425%7D%7D%2C%22widgets%22%3A%7B%7D%7D%2C%22answerArea%22%3A%7B%22type%22%3A%22multiple%22%2C%22options%22%3A%7B%22content%22%3A%22%22%2C%22images%22%3A%7B%7D%2C%22widgets%22%3A%7B%7D%7D%2C%22calculator%22%3Afalse%7D%2C%22itemDataVersion%22%3A%7B%22major%22%3A0%2C%22minor%22%3A1%7D%2C%22hints%22%3A%5B%5D%7D)
and it worked

Didn't test that it only calls onRender a reasonable number of times,
since we only seem to use that prop for sortables, and testing it in
chrome devtools without giving a new onRender was hard

Auditors: alpert