message: Return nullptr if hash is empty
diff: @@ -133,8 +133,10 @@ class MapInterface {
  XodrLaneId& found_lane_id) const;
  RoadCorridorPtr GetRoadCorridor(const std::vector<XodrRoadId>& road_ids,
  const XodrDrivingDirection& driving_direction) {
  - return road_corridors_.at(
  - RoadCorridor::GetHash(driving_direction, road_ids));
  + std::size_t rc_hash = RoadCorridor::GetHash(driving_direction, road_ids);
  + if (road_corridors_.count(rc_hash) == 0)
  + return nullptr;
  + return road_corridors_.at(rc_hash);
  }
  LaneId FindCurrentLane(const Point2d& pt) {
  