Add:创建 flutter go web 版

packages/flutter_web/test/widgets/implicit_animations_test.dart

@@ -0,0 +1,46 @@
+// Copyright 2016 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('BoxConstraintsTween control test', (WidgetTester tester) async {
+    final BoxConstraintsTween tween = BoxConstraintsTween(
+        begin: BoxConstraints.tight(const Size(20.0, 50.0)),
+        end: BoxConstraints.tight(const Size(10.0, 30.0)));
+    final BoxConstraints result = tween.lerp(0.25);
+    expect(result.minWidth, 17.5);
+    expect(result.maxWidth, 17.5);
+    expect(result.minHeight, 45.0);
+    expect(result.maxHeight, 45.0);
+  });
+
+  testWidgets('DecorationTween control test', (WidgetTester tester) async {
+    final DecorationTween tween = DecorationTween(
+        begin: const BoxDecoration(color: Color(0xFF00FF00)),
+        end: const BoxDecoration(color: Color(0xFFFFFF00)));
+    final BoxDecoration result = tween.lerp(0.25);
+    expect(result.color, const Color(0xFF3FFF00));
+  });
+
+  testWidgets('EdgeInsetsTween control test', (WidgetTester tester) async {
+    final EdgeInsetsTween tween = EdgeInsetsTween(
+        begin: const EdgeInsets.symmetric(vertical: 50.0),
+        end: const EdgeInsets.only(top: 10.0, bottom: 30.0));
+    final EdgeInsets result = tween.lerp(0.25);
+    expect(result.left, 0.0);
+    expect(result.right, 0.0);
+    expect(result.top, 40.0);
+    expect(result.bottom, 45.0);
+  });
+
+  testWidgets('Matrix4Tween control test', (WidgetTester tester) async {
+    final Matrix4Tween tween = Matrix4Tween(
+        begin: Matrix4.translationValues(10.0, 20.0, 30.0),
+        end: Matrix4.translationValues(14.0, 24.0, 34.0));
+    final Matrix4 result = tween.lerp(0.25);
+    expect(result, equals(Matrix4.translationValues(11.0, 21.0, 31.0)));
+  });
+}