anchor.diff:      // rely on this. We therefore wrap it into an expectAsync.
       runZoned(expectAsync0(() {
         var zone = Zone.current;
  -      expect(zone, isNot(equals(Zone.root)));
  +      Expect.notEquals(zone, Zone.root);
   
         StreamSubscription<Event> sub;
   
  
positive.code:     sub.cancel();
      invocationCounter = 0;
      element.dispatchEvent(event);
      expect(invocationCounter, isZero);
  
      provider.forTarget(element).listen(handler);
      invocationCounter = 0;
  
negative.code: 
      invocationCounter = 0;
      element.dispatchEvent(event);
      expect(invocationCounter, 0);
  
      var provider = new EventStreamProvider<Event>('test');
  
  