Add:创建 flutter go web 版

packages/flutter_web/test/widgets/scroll_interaction_test.dart

@@ -0,0 +1,41 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'package:flutter_web_test/flutter_web_test.dart';
+import 'package:flutter_web/widgets.dart';
+
+void main() {
+  testWidgets('Scroll flings twice in a row does not crash',
+      (WidgetTester tester) async {
+    await tester.pumpWidget(
+      new Directionality(
+        textDirection: TextDirection.ltr,
+        child: new ListView(
+          children: <Widget>[new Container(height: 100000.0)],
+        ),
+      ),
+    );
+
+    final ScrollableState scrollable =
+        tester.state<ScrollableState>(find.byType(Scrollable));
+
+    expect(scrollable.position.pixels, equals(0.0));
+
+    await tester.flingFrom(
+        const Offset(200.0, 300.0), const Offset(0.0, -200.0), 500.0);
+    await tester.pump();
+    await tester.pump(const Duration(seconds: 5));
+
+    expect(scrollable.position.pixels, greaterThan(0.0));
+
+    final double oldOffset = scrollable.position.pixels;
+
+    await tester.flingFrom(
+        const Offset(200.0, 300.0), const Offset(0.0, -200.0), 500.0);
+    await tester.pump();
+    await tester.pump(const Duration(seconds: 5));
+
+    expect(scrollable.position.pixels, greaterThan(oldOffset));
+  });
+}