Method HasNullCount

cpp/src/parquet/statistics.cc:679–679

  bool HasDistinctCount() const override { return has_distinct_count_; };
  bool HasMinMax() const override { return has_min_max_; }
  bool HasNullCount() const override { return has_null_count_; };

  void IncrementNullCount(int64_t n) override {
    statistics_.null_count += n;