MetricSnapshot convert() {
        for (Map.Entry<Identifier, UntypedMetric> entry : snapshot.entrySet()) {
            Identifier ident = entry.getKey();
            getMap(ident.getLocation()).put(ident.getName(), convert(entry.getValue()));
        }
        Map<MetricDimensions, MetricSet> data = new HashMap<>();
        for (Map.Entry<Point, Map<String, MetricValue>> entry : perPointData.entrySet()) {
            MetricDimensions key = convert(entry.getKey());
            MetricSet newval = new MetricSet(entry.getValue());
            MetricSet old = data.get(key);
            if (old != null) {
                // should not happen, this is bad
                // TODO: consider merging the two MetricSet instances
                log.warning("losing MetricSet when converting for: "+entry.getKey());
            } else {
                data.put(key, newval);
            }
        }
        return new MetricSnapshot(snapshot.getFromMillis(),
                                  snapshot.getToMillis(),
                                  TimeUnit.MILLISECONDS,
                                  data);
    }
Convert simple metrics snapshots into jdisc state snapshots.

@author arnej27959
container-core/src/main/java/com/yahoo/metrics/simple/jdisc/SnapshotConverter.java