presto-main/src/main/java/io/prestosql/cost/ProjectStatsRule.java/ProjectStatsRule/ProjectStatsRule
class ProjectStatsRule:    public ProjectStatsRule(ScalarStatsCalculator scalarStatsCalculator, StatsNormalizer normalizer)
    {
        super(normalizer);
        this.scalarStatsCalculator = requireNonNull(scalarStatsCalculator, "scalarStatsCalculator is null");
    }