message: fix a bug, populate node name before collector::save.
diff: @@ -158,6 +158,7 @@ class StepStatsCuptiTracerAdaptor : public CuptiTraceCollector {
  !annotation_stack.empty()
  ? std::string(annotation_stack.back().name)
  : port::MaybeAbiDemangle(event.name.c_str());
  + ns->set_node_name(activity_name);
  switch (event.type) {
  case CuptiTracerEventType::Kernel: {
  const std::string details = strings::Printf(
  @@ -200,7 +201,6 @@ class StepStatsCuptiTracerAdaptor : public CuptiTraceCollector {
  ns->set_timeline_label(activity_name);
  collector->Save(stream_device, ns);
  }
  - ns->set_node_name(std::move(activity_name));
  }
  }
  }
  