Add second argument support in DOMTokeList.toggle (e.g. for Internet Explorer)

ie-domtokenlist-toggle.js

(function(dtl) {
    if (!dtl) return;
    
    var elem = document.createElement("div");
    div.classList.toggle("test", false);
    if (div.className === "test")
        dtl.prototype.toggle = (function(toggle) {
            return function(cls, force) {
                if (typeof force === "boolean")
                    return this[force ? "add" : "remove"](cls);
                
                return toggle.call(this, cls);
            };
        })(dtl.prototype.toggle);
})(window.DOMTokenList);

var elem = [...] should be var div = [...]