anchor.diff:          return;
         }
         if (options.cfeOnly) return;
  -      _mainLibraryUri = result.rootLibraryUri;
   
         frontendStrategy.registerLoadedLibraries(result);
         for (Uri uri in result.libraries) {
  
positive.code: 
    api.CompilerOutput get outputProvider => _outputProvider;
  
    Uri _mainLibraryUri;
  
    JClosedWorld backendClosedWorldForTesting;
  
  
negative.code:   }
  
    void compileFromKernel(Uri rootLibraryUri, Iterable<Uri> libraries) {
      _userCodeLocations.add(new CodeLocation(rootLibraryUri));
      selfTask.measureSubtask("compileFromKernel", () {
        JClosedWorld closedWorld = selfTask.measureSubtask("computeClosedWorld",
            () => computeClosedWorld(rootLibraryUri, libraries));
  