anchor.diff:  import 'dart:html';
   import 'dart:isolate';
   
  -isolateMain() {
  +childDomIsolate() {
     port.receive((msg, replyTo) {
       if (msg != 'check') {
         replyTo.send('wrong msg: $msg');
  
positive.code:   });
  }
  
  dummy() => print("Bad invocation of top-level function");
  
  main() {
    useHtmlConfiguration();
  
    test('Simple DOM isolate test', () {
      spawnDomFunction(isolateMain).then((sendPort) {
        sendPort.call('check').then(
          expectAsync1((msg) {
            expect(msg, equals('${window.location}'));
          }));
      });
    });
  
    test('Nested DOM isolates test', () {
      spawnDomFunction(isolateMainTrampoline).then((sendPort) {
        sendPort.call('check').then(
          expectAsync1((msg) {
            expect(msg, equals('${window.location}'));
          }));
      });
    });
  
    test('Not function', () {
  
negative.code: 
    test('Masked local function', () {
      var local = 42;
      dummy() => print('Bad invocation of local function: $local');
      expect(() => spawnDomFunction(dummy), throws);
    });
  }
  