message: Enable collective ops in defun
diff: @@ -439,6 +439,7 @@ class PartitionedCallOp : public AsyncOpKernel {
  opts.step_container = ctx->step_container();
  opts.cancellation_manager = ctx->cancellation_manager();
  opts.stats_collector = ctx->stats_collector();
  + opts.collective_executor = ctx->collective_executor();
  // TODO(akshayka): Consider selecting a runner on a per-device basis, i.e.,
  // using device-specific threadpools when available.
  opts.runner = ctx->runner();
  