message: Roll back create_cluster_spec change in estimator until nightly picks up the updated tf.
diff: @@ -183,11 +183,11 @@ def create_in_process_cluster(num_workers,
  protocol='grpc')
  -def create_cluster_spec(test_obj,
  - has_chief=False,
  +def create_cluster_spec(has_chief=False,
  num_workers=1,
  num_ps=0,
  - has_eval=False):
  + has_eval=False,
  + test_obj=None):
  """Create a cluster spec with tasks with unused local ports."""
  if _portpicker_import_error:
  raise _portpicker_import_error # pylint: disable=raising-bad-type
  @@ -207,6 +207,8 @@ def create_cluster_spec(test_obj,
  if has_eval:
  cluster_spec['evaluator'] = ['localhost:%s' % pick_unused_port()]
  except portpicker.NoFreePortFoundError:
  + if test_obj is None:
  + raise
  test_obj.skipTest('Flakes in portpicker library do not represent '
  'TensorFlow errors.')
  return cluster_spec
  