message: Always cast `tf.distributions.Distribution` `_event_shape`, `_batch_shape`.
diff: @@ -593,7 +593,7 @@ class Distribution(_BaseDistribution):
  Returns:
  batch_shape: `TensorShape`, possibly unknown.
  """
  - return self._batch_shape()
  + return tensor_shape.as_shape(self._batch_shape())
  def _event_shape_tensor(self):
  raise NotImplementedError("event_shape_tensor is not implemented")
  @@ -626,7 +626,7 @@ class Distribution(_BaseDistribution):
  Returns:
  event_shape: `TensorShape`, possibly unknown.
  """
  - return self._event_shape()
  + return tensor_shape.as_shape(self._event_shape())
  def is_scalar_event(self, name="is_scalar_event"):
  """Indicates that `event_shape == []`.
  