docs: SaveRestoreState saveRestoreState() {
      List<Statement> saves = new ArrayList<>();
      List<Statement> restores = new ArrayList<>();
      // Iterate backwards so that we restore variables in order of definition which will ensure that
      // derived fields work correctly.
      for (Iterator<Map<VarKey, Variable>> iterator = frames.descendingIterator();
          iterator.hasNext();
          ) {
        Map<VarKey, Variable> frame = iterator.next();
        for (Variable var : frame.values()) {
          saves.add(var.save());
          restores.add(var.restore());
        }
      }
      return new AutoValue_TemplateVariableManager_SaveRestoreState(
          Statement.concat(saves), Statement.concat(restores));
    }