[Extension types guide](https://www.tensorflow.org/guide/extension_type).

## Bug Fixes and Other Changes

*   TF Core:
    *   Random number generation (RNG) system
        *   Add argument `alg` to `tf.random.stateless_*` functions to
            explicitly select the RNG algorithm.
        *   Add `tf.nn.experimental.stateless_dropout`, a stateless version of
            `tf.nn.dropout`.