t measures; only create "measure1" and "measure2", "measureUndefined" is a non-existent
            // measure; give "measure1" a startMark of "navigationStart" and "measure2" a startMark of
            // "responseEnd", this way, "measure1" always come first in a PerformanceEntryList returned from a
            // Performance Timeline accessor
            window.performance.measure(measureName1, "navigationStart");
            window.performance.measure(measureName2, "responseEnd");

            // test th