[web] support iframe role attribute

Author: p-mazhnik

flutter_inappwebview_platform_interface/lib/src/in_app_webview/in_app_webview_settings.dart

@@ -1652,6 +1652,16 @@ as it can cause framerate drops on animations in Android 9 and lower (see [Hybri
   ])
   String? iframeCsp;
 
+  ///A string that reflects the `role` HTML attribute, containing a WAI-ARIA role for the element.
+  @SupportedPlatforms(platforms: [
+    WebPlatform(
+        requiresSameOrigin: false,
+        apiName: "iframe.role",
+        apiUrl:
+            "https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/Roles")
+  ])
+  String? iframeRole;
+
   @ExchangeableObjectConstructor()
   InAppWebViewSettings_({
     this.useShouldOverrideUrlLoading,
@@ -1794,6 +1804,7 @@ as it can cause framerate drops on animations in Android 9 and lower (see [Hybri
     this.iframeReferrerPolicy,
     this.iframeName,
     this.iframeCsp,
+    this.iframeRole,
   }) {
     if (this.minimumFontSize == null)
       this.minimumFontSize = Util.isAndroid ? 8 : 0;

flutter_inappwebview_platform_interface/lib/src/in_app_webview/in_app_webview_settings.g.dart

@@ -230,6 +230,7 @@ class InAppWebViewWebElement implements Disposable {
           iframe.referrerPolicy;
       iframe.name = settings!.iframeName ?? iframe.name;
       iframe.csp = settings!.iframeCsp ?? iframe.csp;
+      iframe.role = settings!.iframeRole ?? iframe.role;
 
       if (settings!.iframeSandbox != null &&
           settings!.iframeSandbox != Sandbox.ALLOW_ALL) {
@@ -470,6 +471,9 @@ class InAppWebViewWebElement implements Disposable {
     if (settings!.iframeCsp != newSettings.iframeCsp) {
       iframe.csp = newSettings.iframeCsp;
     }
+    if (settings!.iframeRole != newSettings.iframeRole) {
+      iframe.role = newSettings.iframeRole;
+    }
 
     if (settings!.iframeSandbox != newSettings.iframeSandbox) {
       var sandbox = newSettings.iframeSandbox;