means that a Gateway is based on the state of the GatewayClass at the time it
          was created and changes to the GatewayClass or associated parameters are not
          propagated down to existing Gateways. This recommendation is intended to
          limit the blast radius of changes to GatewayClass or associated parameters.
          If implementations choose to propagate GatewayClass changes to existing

    states. Specifically, it no longer ever drops the `c` (memory) state of an
    `LSTMStateTuple`. The new behavior leads to proper dropout behavior for
    LSTMs and stacked LSTMs. This bug fix follows recommendations from published
    literature, but is a behavioral change. State dropout behavior may be
    customized via the new `dropout_state_filter_visitor` argument.