Summary: Should also work if eventbase isn't looping

Test Plan: added new unittest

Reviewed By: hans@fb.com

Subscribers: doug, folly-diffs@, yfeldblum, chalfant

FB internal diff: D1984259

Signature: t1:1984259:1428691788:edb89424a48b8071a776d828300b7c1094f1c48f