enum NavigationType {
    "navigate",
    "reload",
    "back_forward",
    "prerender"
};

interface PerformanceNavigationTiming : PerformanceResourceTiming {
    readonly attribute DOMHighResTimeStamp unloadEventStart;
    readonly attribute DOMHighResTimeStamp unloadEventEnd;
    readonly attribute DOMHighResTimeStamp domInteractive;
    readonly attribute DOMHighResTimeStamp domContentLoadedEventStart;
    readonly attribute DOMHighResTimeStamp domContentLoadedEventEnd;
    readonly attribute DOMHighResTimeStamp domComplete;
    readonly attribute DOMHighResTimeStamp loadEventStart;
    readonly attribute DOMHighResTimeStamp loadEventEnd;
    readonly attribute NavigationType      type;
    readonly attribute unsigned short      redirectCount;
    [Default] object toJSON();
};