anchor.diff:  class WebViewController {
     WebViewController._(
       int id,
  -    this._settings,
  -    Set<JavascriptChannel> javascriptChannels,
  -    this._navigationDelegate,
  -    this._onPageFinished,
  +    this._widget,
     ) : _channel = MethodChannel('plugins.flutter.io/webview_$id') {
  -    _updateJavascriptChannelsFromSet(javascriptChannels);
  +    _settings = _WebSettings.fromWidget(_widget);
  +    _updateJavascriptChannelsFromSet(_widget.javascriptChannels);
       _channel.setMethodCallHandler(_onMethodCall);
     }
   
     final MethodChannel _channel;
   
  -  NavigationDelegate _navigationDelegate;
  -
     _WebSettings _settings;
   
  -  PageFinishedCallback _onPageFinished;
  +  WebView _widget;
   
     // Maps a channel name to a channel.
     Map<String, JavascriptChannel> _javascriptChannels =
  
positive.code: class _WebViewState extends State<WebView> {
    final Completer<WebViewController> _controller =
        Completer<WebViewController>();
  
    _WebSettings _settings;
  
    @override
    Widget build(BuildContext context) {
  
negative.code:     // ignore: strong_mode_implicit_dynamic_method
      await _channel.invokeMethod("clearCache");
      return reload();
    }
  
    Future<void> _updateWidget(WebView widget) async {
      _widget = widget;
      await _updateSettings(_WebSettings.fromWidget(widget));
      await _updateJavascriptChannels(widget.javascriptChannels);
    }
  
    Future<void> _updateSettings(_WebSettings setting) async {
  