protected void flattenNoNulls(boolean selectedInUse, int[] sel,
                                int size) {
    if (noNulls) {
      noNulls = false;
      if (selectedInUse) {
        for (int j = 0; j < size; j++) {
          isNull[sel[j]] = false;
        }
      } else {
        Arrays.fill(isNull, 0, size, false);
      }
    }
  }
Sets the isRepeating flag. Recurses over structs and unions so that the
flags are set correctly.
@param isRepeating flag for repeating value.
storage-api/src/java/org/apache/hadoop/hive/ql/exec/vector/ColumnVector.java