if (!status->status.ok()) {
        // Contract is we always delete input_values[i].
        return false;
      }
      // Note: session->session is not modified if Extend() fails, so
      // we only set last_num_graph_nodes if it succeeds.
      session->last_num_graph_nodes = num_nodes;
    } else {
      session->graph->mu.unlock();
    }
  }
  return true;
}

        CreatePerDeviceValues(context, components, device_name, status.get());
    variable->AssignAdd(context, combined_value.get(), status.get());
  }

  // Read the variable and verify that each component has the right modified
  // value.
  {
    TensorHandlePtr read = variable->Read(context, status.get());
    std::array<TensorHandlePtr, 2> components;
    ExtractPerDeviceValues(context, read.get(), &components, status.get());