message: Add a test case for ValueError raised by serialization.serialize_feature_column
diff: @@ -1553,6 +1553,8 @@ class SequenceNumericColumnTest(test.TestCase, parameterized.TestCase):
  self.assertEqual(column.shape, (2,))
  self.assertEqual(column.default_value, 3)
  self.assertEqual(column.normalizer_fn(3), 45)
  + with self.assertRaises(ValueError):
  + serialization.serialize_feature_column(int())
  def test_parents(self):
  """Tests parents attribute of column."""
  