Names are case insensitive right? Otherwise things would be wild
 `o_a_nimation` vs `o_T_ransition`
`_MS_Animation` vs `_ms_Transition`

By the way I think there's a problem in line 88.
If the prefix is `Moz` you add again the standard events `"transitionend", "animationstart", "animationiteration", "animationend"` that you already have in `this.delegatedOnBody`. Boesn't this add 2 event listeners?

My suggestion is to modify `checkCSSPrefix` to detect also standard-compliant transition support. In case of `Moz` and `Standard` you add standard events. By doing so we don't add animation events on IE7..9