Obsolete CubicBezierEasing (#13137)

#Conflicts:
#	src/Avalonia.Base/Animation/Easings/CubicBezierEasing.cs

src/Avalonia.Base/Animation/Easings/CubicBezierEasing.cs

@@ -2,26 +2,16 @@
 
 namespace Avalonia.Animation.Easings;
 
-public class CubicBezierEasing : IEasing
+[Obsolete("Use SplineEasing instead")]
+public sealed class CubicBezierEasing : IEasing
 {
-    private CubicBezier _bezier;
-    //cubic-bezier(0.25, 0.1, 0.25, 1.0)
-    internal CubicBezierEasing(Point controlPoint1, Point controlPoint2)
+    private CubicBezierEasing()
     {
-        ControlPoint1 = controlPoint1;
-        ControlPoint2 = controlPoint2;
-        if (controlPoint1.X < 0 || controlPoint1.X > 1 || controlPoint2.X < 0 || controlPoint2.X > 1)
-            throw new ArgumentException();
-        _bezier = new CubicBezier(controlPoint1.X, controlPoint1.Y, controlPoint2.X, controlPoint2.Y);
     }
 
     public Point ControlPoint2 { get; set; }
     public Point ControlPoint1 { get; set; }
-
-    internal static IEasing Ease { get; } = new CubicBezierEasing(new Point(0.25, 0.1), new Point(0.25, 1));
 
     double IEasing.Ease(double progress)
-    {
-        return _bezier.Solve(progress);
-    }
-}
+        => throw new NotSupportedException();
+}

src/Avalonia.Base/Rendering/Composition/Compositor.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Avalonia.Animation;
 using Avalonia.Animation.Easings;
 using Avalonia.Media;
 using Avalonia.Metadata;
@@ -85,7 +86,7 @@ internal Compositor(IRenderLoop loop, IPlatformGraphics? gpu,
             _server = new ServerCompositor(loop, gpu, _batchObjectPool, _batchMemoryPool);
             _triggerCommitRequested = () => scheduler.CommitRequested(this);
 
-            DefaultEasing = new CubicBezierEasing(new Point(0.25f, 0.1f), new Point(0.25f, 1f));
+            DefaultEasing = new SplineEasing(new KeySpline(0.25, 0.1, 0.25, 1.0));
         }
 
         /// <summary>