feat(autolayout): colapsed children don't count in the measure (#663)

(cherry picked from commit 4784666)

src/Uno.Toolkit.UI/Controls/AutoLayout/AutoLayout.Layouting.Arrange.cs

@@ -47,6 +47,11 @@ protected override Size ArrangeOverride(Size finalSize)
 			var child = children[i];
 			var calculatedChild = _calculatedChildren[i];
 
+			if (child is FrameworkElement { Visibility: Visibility.Collapsed })
+			{
+				continue;
+			}
+
 			if (!ReferenceEquals(child, calculatedChild.Element))
 			{
 				// Invalid calculated child, invalidate measure and wait for next pass to fix this.
@@ -152,6 +157,11 @@ protected override Size ArrangeOverride(Size finalSize)
 				continue; // next child, current offset remains unchanged
 			}
 
+			if (children[i] is FrameworkElement { Visibility: Visibility.Collapsed })
+			{
+				continue;
+			}
+
 			// Calculate the length of the child (size in the panel orientation)
 
 			// Length depends on the role of the child

src/Uno.Toolkit.UI/Controls/AutoLayout/AutoLayout.Layouting.Measure.cs

@@ -94,6 +94,7 @@ protected override Size MeasureOverride(Size availableSize)
 			// 8b. Calculate the desired size of the panel, when there's at least one filled child
 			var stackedChildrenDesiredSize =
 				_calculatedChildren!
+					.Where(child => child.IsVisible)
 					.Select(c => c.MeasuredLength)
 					.Sum()
 				+ totalSpacingSize;
@@ -212,7 +213,7 @@ private void MeasureFixedChildren(
 		{
 			var calculatedChild = _calculatedChildren[i];
 
-			if (calculatedChild.Role != AutoLayoutRole.Fixed)
+			if (calculatedChild.Role != AutoLayoutRole.Fixed || !calculatedChild.IsVisible)
 			{
 				continue;
 			}
@@ -243,7 +244,7 @@ private void MeasureHugChildren(
 		{
 			var calculatedChild = _calculatedChildren![i];
 
-			if (calculatedChild.Role != AutoLayoutRole.Hug)
+			if (calculatedChild.Role != AutoLayoutRole.Hug || !calculatedChild.IsVisible)
 			{
 				continue;
 			}
@@ -282,7 +283,7 @@ private bool MeasureFilledChildren(
 		{
 			var child = _calculatedChildren![i];
 
-			if (child.Role == AutoLayoutRole.Filled)
+			if (child.Role == AutoLayoutRole.Filled || child.IsVisible)
 			{
 				filledChildrenCount++;
 			}
@@ -299,7 +300,7 @@ private bool MeasureFilledChildren(
 		for (var i = 0; i < _calculatedChildren!.Length; i++)
 		{
 			var child = _calculatedChildren![i];
-			if (child.Role != AutoLayoutRole.Filled)
+			if (child.Role != AutoLayoutRole.Filled || !child.IsVisible)
 			{
 				continue;
 			}
@@ -446,8 +447,11 @@ public CalculatedChildren(UIElement element, AutoLayoutRole role, double measure
 			Element = element;
 			Role = role;
 			MeasuredLength = measuredLength;
+			IsVisible = element.Visibility == Visibility.Visible;
 		}
 
+		internal bool IsVisible { get; }
+
 		internal UIElement Element { get; }
 
 		/// <summary>