presto-main/src/main/java/io/prestosql/sql/planner/iterative/rule/TransformCorrelatedInPredicateToJoin.java/TransformCorrelatedInPredicateToJoin/countWithFilter
class TransformCorrelatedInPredicateToJoin:    private AggregationNode.Aggregation countWithFilter(Symbol filter)
    {
        return new AggregationNode.Aggregation(
                countFunction,
                ImmutableList.of(),
                false,
                Optional.of(filter),
                Optional.empty(),
                Optional.empty()); /* mask */
    }