message: Fix use-after-free bug in Swisstable usage.
diff: @@ -47,6 +47,9 @@ Status DiscoverDataDependencies(
  instance_keys->push_back(instance_key);
  VLOG(2) << "collective node " << node->DebugString();
  }
  + // Avoid reference invalidation of `node_deps`.
  + data_dependencies->reserve(data_dependencies->size() + 1 +
  + node->out_edges().size());
  const auto& node_deps = (*data_dependencies)[node];
  for (const Edge* out_edge : node->out_edges()) {
  auto& child_deps = (*data_dependencies)[out_edge->dst()];
  