Update platform_interface.dart

packages/webview_flutter/lib/platform_interface.dart

@@ -420,6 +420,8 @@ class CreationParams {
   /// The `autoMediaPlaybackPolicy` parameter must not be null.
   CreationParams({
     this.initialUrl,
+    this.html,
+    this.baseUrl,
     this.webSettings,
     this.javascriptChannelNames,
     this.userAgent,
@@ -431,7 +433,8 @@ class CreationParams {
   ///
   /// When null the webview will be created without loading any page.
   final String initialUrl;
-
+  final String baseUrl;
+  final String html;
   /// The initial [WebSettings] for the new webview.
   ///
   /// This can later be updated with [WebViewPlatformController.updateSettings].