void successfulResponse() {
        setTimeToFirstByteFirstTime();

        long requestLatency = getRequestLatency();

        metric.set(MetricDefinitions.TOTAL_SUCCESSFUL_LATENCY, requestLatency, context);

        metric.add(MetricDefinitions.NUM_SUCCESSFUL_RESPONSES, 1, context);
    }
Responsible for metric reporting for JDisc http request handler support.
@author Tony Vaagenes
container-core/src/main/java/com/yahoo/jdisc/http/server/jetty/RequestMetricReporter.java