message: Support `sample_weights` in `model_to_estimator`.
diff: @@ -40,6 +40,27 @@ def model_to_estimator(
  [Creating estimators from Keras
  Models](https://tensorflow.org/guide/estimators#model_to_estimator).
  + __Sample Weights__
  + Estimators returned by `model_to_estimator` are configured to handle sample
  + weights (similar to `keras_model.fit(x, y, sample_weights)`). To pass sample
  + weights when training or evaluating the Estimator, the first item returned by
  + the input function should be a dictionary with keys `features` and
  + `sample_weights`. Example below:
  +
  + ```
  + keras_model = tf.keras.Model(...)
  + keras_model.compile(...)
  +
  + estimator = tf.keras.estimator.model_to_estimator(keras_model)
  +
  + def input_fn():
  + return dataset_ops.Dataset.from_tensors(
  + ({'features': features, 'sample_weights': sample_weights},
  + targets))
  +
  + estimator.train(input_fn, steps=1)
  + ```
  +
  Args:
  keras_model: A compiled Keras model object. This argument is mutually
  exclusive with `keras_model_path`.
  