presto-main/src/main/java/io/prestosql/sql/planner/optimizations/OptimizeMixedDistinctAggregations.java/OptimizeMixedDistinctAggregations/OptimizeMixedDistinctAggregations
class OptimizeMixedDistinctAggregations:    public OptimizeMixedDistinctAggregations(Metadata metadata)
    {
        this.metadata = metadata;
    }