message: Change the keras loss_scale_optimizer to use public TF API.
diff: @@ -323,7 +323,7 @@ class _DynamicLossScaleState(trackable.Trackable):
  def __call__(self):
  """Returns the current loss scale as a scalar `float32` tensor."""
  - return ops.convert_to_tensor(self._current_loss_scale)
  + return ops.convert_to_tensor_v2_with_dispatch(self._current_loss_scale)
  def update(self, grads):
  """Updates the value of the loss scale.
  @@ -567,9 +567,10 @@ class LossScaleOptimizer(_DelegatingTrackableMixin, optimizer_v2.OptimizerV2):
  def loss_scale(self):
  """The current loss scale as a float32 scalar tensor."""
  if isinstance(self._loss_scale, _DynamicLossScaleState):
  - return ops.convert_to_tensor(self._loss_scale.current_loss_scale)
  + return ops.convert_to_tensor_v2_with_dispatch(
  + self._loss_scale.current_loss_scale)
  else:
  - return ops.convert_to_tensor(self._loss_scale)
  + return ops.convert_to_tensor_v2_with_dispatch(self._loss_scale)
  @property
  def dynamic_counter(self):
  