setImmedate polyfill based on http://dbaron.org/log/20100309-faster-timeouts

setImmediate.js

(function() {
	var timeouts = [];
	var messageName = "zero-timeout-message";

	function handleMessage(event) {
		if (event.source === window && event.data === messageName) {
			event.stopPropagation();
			if (timeouts.length > 0) {
				var fn = timeouts.shift();
				fn();
			}
		}
	}

	if (!window.setImmediate) {
		window.setImmediate = function(fn) {
			timeouts.push(fn);
			window.postMessage(messageName, "*");
		}
		window.addEventListener("message", handleMessage, true);
	}
}());