My window.requestAnimationFrame shim

utils.js

if (!window.requestAnimationFrame) {
    window.requestAnimationFrame = (window.webkitRequestAnimationFrame ||
                                    window.mozRequestAnimationFrame ||
                                    window.oRequestAnimationFrame ||
                                    window.msRequestAnimationFrame ||
                                    function (callback) {
                                        return window.setTimeout(callback, 1000/60);
                                    });
}

if (!window.cancelRequestAnimationFrame) {
    window.cancelRequestAnimationFrame = (window.cancelAnimationFrame ||
                                          window.webkitCancelRequestAnimationFrame ||
                                          window.mozCancelRequestAnimationFrame ||
                                          window.oCancelRequestAnimationFrame ||
                                          window.msCancelRequestAnimationFrame ||
                                          window.clearTimeout);
}