message: Make nullptr safe
diff: @@ -61,9 +61,15 @@ struct RoadCorridor {
  LaneCorridorPtr current_lane_corr = GetCurrentLaneCorridor(pt);
  LanePtr left_lane = current_lane_corr->GetCurrentLane(pt)->GetLeftLane();
  LanePtr right_lane = current_lane_corr->GetCurrentLane(pt)->GetRightLane();
  + LaneId left_lane_id = 10000000;
  + LaneId right_lane_id = 10000000;
  + if (left_lane)
  + left_lane_id = left_lane->get_id();
  + if (right_lane)
  + right_lane_id = right_lane->get_id();
  return std::make_pair(
  - GetLaneCorridor(left_lane->get_id()),
  - GetLaneCorridor(right_lane->get_id()));
  + GetLaneCorridor(left_lane_id),
  + GetLaneCorridor(right_lane_id));
  }
  static std::size_t GetHash(
  const std::vector<XodrRoadId>& road_ids) {
  