try to add linux webview support

lib/component/webview/webview_controller.dart

@@ -0,0 +1,61 @@
+
+import 'package:flutter_inappwebview/flutter_inappwebview.dart';
+import 'package:nowser/component/webview/webview_controller_interface.dart';
+
+class WebviewController extends WebviewControllerInterface {
+
+  InAppWebViewController controller;
+
+  WebviewController(this.controller);
+
+  @override
+  Future<void> reload() async {
+    await controller.reload();
+  }
+
+  @override
+  Future<void> goBack() async {
+    await controller.goBack();
+  }
+
+  @override
+  Future<bool> canGoBack() async {
+    return await controller.canGoBack();
+  }
+
+  @override
+  Future<void> goForward() async {
+    await controller.goForward();
+  }
+
+  @override
+  Future<Uri?> getUrl() async {
+    var webUrl = await controller.getUrl();
+    try {
+      if (webUrl != null) {
+        return webUrl.uriValue;
+      }
+    } catch (e) {}
+    return null;
+  }
+
+  @override
+  Future<String?> getFavicon() async {
+    var favicons = await controller.getFavicons();
+    if (favicons.isNotEmpty) {
+      return favicons.first.url.toString();
+    }
+    return null;
+  }
+
+  @override
+  Future<void> loadUrl(String url) async {
+    await controller.loadUrl(urlRequest: URLRequest(url: WebUri(url)));
+  }
+  
+  @override
+  Future<String?> getTitle() async {
+    return controller.getTitle();
+  }
+
+}