message: const to appease the overlord
diff: @@ -235,7 +235,7 @@ public:
  }
  private:
  - FileSystem *FindFileSystem(string path) {
  + FileSystem *FindFileSystem(const string &path) {
  for (auto &handler : protocol_handler_fss) {
  if (path.rfind(handler.first, 0) == 0) {
  return handler.second.get();
  