message: Disable keras correctness test for default distribution strategy.
diff: @@ -26,6 +26,7 @@ from tensorflow.contrib.distribute.python import mirrored_strategy
  from tensorflow.contrib.distribute.python import tpu_strategy
  from tensorflow.python import keras
  from tensorflow.python.data.ops import dataset_ops
  +from tensorflow.python.distribute import distribute_lib
  from tensorflow.python.distribute import values
  from tensorflow.python.eager import test
  from tensorflow.python.estimator import keras as keras_lib
  @@ -1305,6 +1306,11 @@ class TestDistributionStrategyCorrectness(test.TestCase,
  @combinations.generate(strategy_and_input_combinations())
  def test_correctness(self, distribution, use_numpy, use_validation_data):
  + # TODO(b/121224478): This test is flaky with default strategy. Remove this
  + # once the issue is fixed.
  + if isinstance(distribution, distribute_lib._DefaultDistributionStrategy): # pylint: disable=protected-access
  + self.skipTest('Disable the test for default strategy.')
  +
  with self.cached_session():
  default_tolerance = 1e-5
  tol_table = {}
  