message: Disable lower functional ops for TFRT runtime.
  V1 Control flows are not supported by TFRT.
diff: @@ -117,11 +117,12 @@ Status LowerFunctionalOpsPass::Run(
  : !HasArgsOrRetvals(*g);
  // We disable lowering control flow to switch/merge variants for the
  - // single-threaded executor, which does not support it.
  + // single-threaded executor and TFRT runtime, which does not support it.
  const bool functional_control_flow =
  options.session_options &&
  (options.session_options->config.experimental().executor_type() ==
  - "SINGLE_THREADED_EXECUTOR");
  + "SINGLE_THREADED_EXECUTOR" ||
  + options.session_options->config.experimental().use_tfrt());
  // Returns true if `node` will be used for XLA compilation.
  const auto used_by_xla = [](Node* node) -> bool {
  