anchor.diff:      throw new ArgumentError("Arguments to main must be a List: $args");
     }
     _globalState = new _Manager(entry);
  +  _globalState._initialize();
   
     // Don't start the main loop again, if we are in a worker.
     if (_globalState.isWorker) return;
  
positive.code:     }
      // A worker has no script tag - so get an url from a stack-trace.
      if (_globalState.isWorker) return computeThisScriptFromTrace();
      return null;
    }
  
  
negative.code:   /** The entry point given by [startRootIsolate]. */
    final Function entry;
  
    _Manager(this.entry);
  
    _initialize() {
      _nativeDetectEnvironment();
      topEventLoop = new _EventLoop();
      isolates = new Map<int, _IsolateContext>();
  