Function UnsafeAppendNull

cpp/src/arrow/array/builder_primitive.h:545–548

  }

  void UnsafeAppendNull() {
    data_builder_.UnsafeAppend(false);
    UnsafeAppendToBitmap(false);
  }

  void UnsafeAppend(const uint8_t val) { UnsafeAppend(val != 0); }