Chrome桌面提醒功能，兼容新老版本，firefox最新版本也通过

Chrome新版升级api，与w3一致，为了兼容，代码如下：

//桌面提醒
function notify(title, content) {
        
        if(!title && !content){
            title = "桌面提醒";
            content = "您看到此条信息桌面提醒设置成功";
        }
        var iconUrl = "/images/send_ok.png";
        
        if (window.webkitNotifications) {
            //chrome老版本
            if (window.webkitNotifications.checkPermission() == 0) {
                var notif = window.webkitNotifications.createNotification(iconUrl, title, content);
                notif.display = function() {}
                notif.onerror = function() {}
                notif.onclose = function() {}
                notif.onclick = function() {this.cancel();}
                notif.replaceId = 'Meteoric';
                notif.show();
            } else {
                window.webkitNotifications.requestPermission($jy.notify);
            }
        }
        else if("Notification" in window){
            // 判断是否有权限
            if (Notification.permission === "granted") {
                var notification = new Notification(title, {
                    "icon": iconUrl,
                    "body": content,
                });
            }
            //如果没权限，则请求权限
            else if (Notification.permission !== 'denied') {
                Notification.requestPermission(function(permission) {
                    // Whatever the user answers, we make sure we store the
                    // information
                    if (!('permission' in Notification)) {
                        Notification.permission = permission;
                    }
                    //如果接受请求
                    if (permission === "granted") {
                        var notification = new Notification(title, {
                            "icon": iconUrl,
                            "body": content,
                        });
                    }
                });
            }
        }
    }