code: public static Result createResultForStage1(Result result) {
      VariableMap emptyVariableMap = new VariableMap(ImmutableMap.of());
      return new Result(
          result.errors,
          result.warnings,
          emptyVariableMap,
          emptyVariableMap,
          emptyVariableMap,
          null,
          null,
          "",
          null,
          null,
          null);
    }
docs: Returns an almost empty result that is used for multistage compilation.
  
  <p>For multistage compilations, Result for stage1 only cares about errors and warnings. It is
  unnecessary to write all of other results in the disk.