delegate.js

function delegate(element, eventName, selector, handler) {
    var el = null;

    element.addEventListener(eventName, function delegatedListener(e) {
        el = e.target;
        while (el !== element && el.parentNode) {
            if (el.nodeType === 1 && selectorMatches(el, selector)) {
                handler(e, el);
                break;
            }
            el = el.parentNode;
        }
    }, false);
}

matches.js

function selectorMatches(el, selector) {
	var p = Element.prototype;
	var f = p.matches || p.webkitMatchesSelector || p.mozMatchesSelector || p.msMatchesSelector || function(s) {
		return [].indexOf.call(document.querySelectorAll(s), this) !== -1;
	};
	return f.call(el, selector);
}