presto-main/src/main/java/io/prestosql/operator/aggregation/state/HyperLogLogStateFactory.java/HyperLogLogStateFactory/getGroupedStateClass
class HyperLogLogStateFactory:    @Override
    public Class<? extends HyperLogLogState> getGroupedStateClass()
    {
        return GroupedHyperLogLogState.class;
    }