component/emitter — pull request #25 by MatthewMueller (2013-06-29 22:21:51+00:00)
Title: emitter.off(event, undefined) should remove all listeners

Allows for better integration with frameworks.

I ran into it when unsubscribing from a reactive event, because we pass `fn` into `.off(event, fn)` regardless of if it's defined or not.