that can triggerred by `multiply_linear_by_lr` allowing a learning rate
        of zero.

### `tf.data`:

*   `tf.data.experimental.dense_to_ragged_batch` works correctly with tuples.
*   `tf.data.experimental.dense_to_ragged_batch` to output variable ragged rank.
*   `tf.data.experimental.cardinality` is now a method on `tf.data.Dataset`.
*   `tf.data.Dataset` now supports `len(Dataset)` when the cardinality is