anchor.diff:        '_Logging',
         '_Service',
       ];
  -    await Future.wait(streamIds.map((id) => service.streamListen(id)));
  +
  +    await Future.wait(streamIds.map((String id) async {
  +      try {
  +        await service.streamListen(id);
  +      } catch (e) {
  +        print("Service client stream not supported: '$id'");
  +        print('  $e');
  +      }
  +    }));
     }
   
     void vmServiceClosed() {
  
positive.code: 
  class VmServiceCapabilities {
    VmServiceCapabilities(this.version);
    final Version version;
  
    bool get supportsGetScripts =>
  
negative.code:   final Completer<Null> serviceAvailable = Completer();
  
    VmServiceCapabilities _serviceCapabilities;
  
    Future<VmServiceCapabilities> get serviceCapabilities async {
      if (_serviceCapabilities == null) {
        await serviceAvailable.future;
  