chore: Adjust border clipping

src/Uno.UI/UI/Xaml/Controls/Border/BorderLayerRenderer.iOSmacOS.cs

@@ -289,17 +289,15 @@ GradientBrush gradientBorder when gradientBorder.CanApplyToBorder(cornerRadius)
 				}
 			}
 
-			parent.Mask = new CAShapeLayer()
+			foreach (var sublayer in sublayers)
 			{
-				Path = outerPath,
-				Frame = area,
-				// We only use the fill color to create the mask area
-				FillColor = _Color.White.CGColor,
-			};
-
-			if (owner != null)
-			{
-				owner.ClippingIsSetByCornerRadius = true;
+				sublayer.Mask = new CAShapeLayer()
+				{
+					Path = outerPath,
+					Frame = area,
+					// We only use the fill color to create the mask area
+					FillColor = _Color.White.CGColor,
+				};
 			}
 
 			updatedBoundsPath = outerPath;
@@ -427,13 +425,16 @@ GradientBrush gradientBorder when gradientBorder.CanApplyToBorder(cornerRadius)
 			sublayers.Add(backgroundLayer);
 			parent.InsertSublayer(backgroundLayer, insertionIndex);
 
-			parent.Mask = new CAShapeLayer()
+			foreach (var sublayer in sublayers)
 			{
-				Path = outerPath,
-				Frame = area,
-				// We only use the fill color to create the mask area
-				FillColor = _Color.White.CGColor,
-			};
+				sublayer.Mask = new CAShapeLayer()
+				{
+					Path = outerPath,
+					Frame = area,
+					// We only use the fill color to create the mask area
+					FillColor = _Color.White.CGColor,
+				};
+			}
 
 			updatedBoundsPath = outerPath;
 		}
@@ -445,11 +446,6 @@ GradientBrush gradientBorder when gradientBorder.CanApplyToBorder(cornerRadius)
 				sl.RemoveFromSuperLayer();
 				sl.Dispose();
 			}
-
-			if (owner != null)
-			{
-				owner.ClippingIsSetByCornerRadius = false;
-			}
 		}
 		);
 		return disposables;

src/Uno.UI/UI/Xaml/UIElement.iOS.cs

@@ -47,16 +47,11 @@ public override void MovedToWindow()
 			}
 		}
 
-		internal bool ClippingIsSetByCornerRadius { get; set; }
-
 		private void SetClipPlatform(Rect? totalLogicalClip)
 		{
 			if (totalLogicalClip is null)
 			{
-				if (!ClippingIsSetByCornerRadius)
-				{
-					this.Layer.Mask = null;
-				}
+				this.Layer.Mask = null;
 				return;
 			}
 

src/Uno.UI/UI/Xaml/UIElement.macOS.cs

@@ -27,8 +27,6 @@ public UIElement()
 			UpdateHitTest();
 		}
 
-		internal bool ClippingIsSetByCornerRadius { get; set; }
-
 		partial void OnOpacityChanged(DependencyPropertyChangedEventArgs args)
 		{
 			// Don't update the internal value if the value is being animated.
@@ -253,13 +251,10 @@ private void SetClipPlatform(Rect? totalLogicalClip)
 		{
 			if (totalLogicalClip is null)
 			{
-				if (!ClippingIsSetByCornerRadius)
+				var emptyClipLayer = Layer;
+				if (emptyClipLayer != null)
 				{
-					var emptyClipLayer = Layer;
-					if (emptyClipLayer != null)
-					{
-						emptyClipLayer.Mask = null;
-					}
+					emptyClipLayer.Mask = null;
 				}
 				return;
 			}