Determine the correct CSS3 transition end event name.

transitionEndEventName.js

var transitionEndEventName = (function() {
    var i,
        undefined,
        el = document.createElement('div'),
        transitions = {
            'transition':'transitionend',
            'OTransition':'otransitionend',  // oTransitionEnd in very old Opera
            'MozTransition':'transitionend',
            'WebkitTransition':'webkitTransitionEnd'
        };

    for (i in transitions) {
        if (transitions.hasOwnProperty(i) && el.style[i] !== undefined) {
            return transitions[i];
        }
    }

    //TODO: throw 'TransitionEnd event is not supported in this browser'; 
})();