anchor.diff:  
   Task createDart2JsTask(List<String> inputs, {String output: null,
     String packageRoot: null, bool minify: false, bool allowUnsafeEval: true,
  -  bool liveTypeAnalysis: false, rejectDeprecatedFeatures: false}) {
  +  bool liveTypeAnalysis: true, bool rejectDeprecatedFeatures: false}) {
     return new Task.async((context) {
       final futureFuncs = inputs
           .map((p) => () => _dart2js(context, p,
  
positive.code: 
  Future<bool> _dart2js(TaskContext ctx, String file, {String output: null,
    String packageRoot: null, bool minify: false, bool allowUnsafeEval: true,
    bool liveTypeAnalysis: false, rejectDeprecatedFeatures: false}) {
  
    if(output == null) {
      output = "${file}.js";
  
negative.code:                 "--out=$output",
                  file];
  
    if(liveTypeAnalysis == false) {
      args.add('--disable-native-live-type-analysis');
    }
  
    if(rejectDeprecatedFeatures) {
  