@Test
  public void testIfExtendedCellImplemented() {
    // Verify if ExtendedCell interface is implemented
    ExtendedCell ec = (ExtendedCell) ic0;
    ec.deepClone(); // Do something with ec
  }
Verify getXXXArray() and getXXXLength() when family/qualifier/value/tags are null. Should have
the same behaviors as {@link KeyValue}.
hbase-common/src/test/java/org/apache/hadoop/hbase/TestIndividualBytesFieldCell.java