anchor.diff:      }
     }
   
  -  Future<void> _addServiceExtension(String name) async {
  +  Future<void> _addServiceExtension(String name) {
       final streamController = _getServiceExtensionController(name);
   
       _serviceExtensions.add(name);
  
positive.code:     }
      _firstFrameEventReceived = true;
  
      for (String extension in _pendingServiceExtensions) {
        await _addServiceExtension(extension);
      }
      extensionStatesUpdated.complete();
      _pendingServiceExtensions.clear();
    }
  
    Future<void> _addRegisteredExtensionRPCs(IsolateRef isolateRef) async {
  
negative.code:       // extension. This will restore extension states on the device after a hot
        // restart. [_enabledServiceExtensions] will be empty on page refresh or
        // initial start.
        return _callServiceExtension(name, _enabledServiceExtensions[name].value);
      } else {
        // Set any extensions that are already enabled on the device. This will
        // enable extension states in DevTools on page refresh or initial start.
        return _restoreExtensionFromDevice(name);
      }
    }
  
  