public GaugeMetric newWithPreservedLastValue() {
        // min/max set to enforce update of these values on first call to add()
        return new GaugeMetric(last, Double.MIN_VALUE, Double.MAX_VALUE, 0, 0, Optional.empty());
    }
Create a partial clone of this gauge where the value of 'last' is
carried over to the new gauge with all other fields left at defaults
(0 for count and sum, biggest possible double for min, smallest possible
double for max). Note that since count is 0, these extreme values will
never be output from the min/max getters as these will return 'last'
in this case.
@return A new gauge instance
container-core/src/main/java/com/yahoo/container/jdisc/state/GaugeMetric.java