Reorganise tests and add restart step

osu.Game.Tests/Visual/Menus/IntroTestScene.cs

@@ -0,0 +1,66 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using System.Collections.Generic;
+using NUnit.Framework;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Screens;
+using osu.Game.Screens;
+using osu.Game.Screens.Menu;
+using osuTK;
+using osuTK.Graphics;
+
+namespace osu.Game.Tests.Visual.Menus
+{
+    [TestFixture]
+    public abstract class IntroTestScene : OsuTestScene
+    {
+        public override IReadOnlyList<Type> RequiredTypes => new[]
+        {
+            typeof(OsuLogo),
+            typeof(StartupScreen),
+            typeof(IntroScreen),
+            typeof(OsuScreen),
+            typeof(IntroTestScene),
+        };
+
+        [Cached]
+        private OsuLogo logo;
+
+        protected IntroTestScene()
+        {
+            Drawable introStack = null;
+
+            Children = new Drawable[]
+            {
+                new Box
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    Depth = float.MaxValue,
+                    Colour = Color4.Black,
+                },
+                logo = new OsuLogo
+                {
+                    Alpha = 0,
+                    RelativePositionAxes = Axes.Both,
+                    Depth = float.MinValue,
+                    Position = new Vector2(0.5f),
+                }
+            };
+
+            AddStep("restart sequence", () =>
+            {
+                introStack?.Expire();
+                Add(introStack = new OsuScreenStack(CreateScreen())
+                {
+                    RelativeSizeAxes = Axes.Both,
+                });
+            });
+        }
+
+        protected abstract IScreen CreateScreen();
+    }
+}