add FlutterWeb with WidgetsBindingIntegration sample tab

Author: denrase

docs/platforms/flutter/index.mdx

@@ -46,7 +46,6 @@ dependencies:
 
 Configuration should happen as early as possible in your application's lifecycle.
 
-
 ```dart {"onboardingOptions": {"performance": "8-10", "profiling": "11-14"}}
 import 'package:flutter/widgets.dart';
 import 'package:sentry_flutter/sentry_flutter.dart';
@@ -71,6 +70,40 @@ Future<void> main() async {
 }
 ```
 
+```dart {tabTitle:FlutterWeb with WidgetsBindingIntegration}  {"onboardingOptions": {"performance": "13-15", "profiling": "16-19"}}
+import 'package:flutter/widgets.dart';
+import 'package:sentry_flutter/sentry_flutter.dart';
+
+Future<void> main() async {
+  Sentry.runZonedGuarded(() async {
+    WidgetsBinding.ensureInitialized();
+
+    // Errors before init will not be handled by Sentry
+
+    await SentryFlutter.init(
+      (options) {
+        options.dsn = '___PUBLIC_DSN___';
+        // Set tracesSampleRate to 1.0 to capture 100% of transactions for tracing.
+        // We recommend adjusting this value in production.
+        options.tracesSampleRate = 1.0;
+        // The sampling rate for profiling is relative to tracesSampleRate
+        // Setting to 1.0 will profile 100% of sampled transactions:
+        // Note: Profiling alpha is available for iOS and macOS since SDK version 7.12.0
+        options.profilesSampleRate = 1.0;
+      },
+      appRunner: () => runApp(MyApp()),
+    );
+  } (error, stackTrace) {
+    // Automatically sends errors to Sentry, no need to do any
+    // captureException calls on your part.
+    // On top of that, you can do your own custom stuff in this callback.
+  });
+
+  // you can also configure SENTRY_DSN, SENTRY_RELEASE, SENTRY_DIST, and
+  // SENTRY_ENVIRONMENT via Dart environment variable (--dart-define)
+}
+```
+
 ## Verify
 
 Verify that your app is sending events to Sentry by adding the following snippet, which includes an intentional error. You should see the error reported in Sentry within a few minutes.