fix(XamlReader): Update invalid collection error message, validate Ta…

…bView setter.

src/Uno.UI.Tests/Windows_UI_Xaml_Markup/XamlReaderTests/Given_XamlReader.cs

@@ -715,6 +715,17 @@ public void When_StaticResource_SystemTypes()
 			Assert.AreEqual("Result is 42", r.Resources["myString"]);
 		}
 
+		[TestMethod]
+		public void When_IList_TabView()
+		{
+			var s = GetContent(nameof(When_IList_TabView));
+			var r = Windows.UI.Xaml.Markup.XamlReader.Load(s) as UserControl;
+
+			var tabView1 = r.FindName("tabView1") as Microsoft.UI.Xaml.Controls.TabView;
+
+			Assert.AreEqual(2, tabView1.TabItems.Count);
+		}
+
 		private string GetContent(string testName)
 		{
 			var assembly = this.GetType().Assembly;

src/Uno.UI.Tests/Windows_UI_Xaml_Markup/XamlReaderTests/When_IList_TabView.xamltest

@@ -0,0 +1,23 @@
+<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+      xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+      xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+      xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+      xmlns:wux="using:Microsoft.Toolkit.Uwp.UI.Controls"
+      xmlns:muxc="using:Microsoft.UI.Xaml.Controls"
+      Name="rootPage"
+      mc:Ignorable="d">
+
+  <muxc:TabView x:Name="tabView1" HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
+	<muxc:TabViewItem Header="Home" IsClosable="False">
+	  <muxc:TabViewItem.IconSource>
+		<muxc:SymbolIconSource Symbol="Home" />
+	  </muxc:TabViewItem.IconSource>
+	</muxc:TabViewItem>
+	<muxc:TabViewItem Header="Document 1">
+	  <muxc:TabViewItem.IconSource>
+		<muxc:SymbolIconSource Symbol="Document" />
+	  </muxc:TabViewItem.IconSource>
+	</muxc:TabViewItem>
+  </muxc:TabView>
+
+</Page>

src/Uno.UI/UI/Xaml/Markup/Reader/XamlObjectBuilder.cs

@@ -426,7 +426,7 @@ private void ProcessMemberElements(object instance, XamlMemberDefinition member,
 				}
 				else
 				{
-					throw new InvalidOperationException("Invalid collection");
+					throw new InvalidOperationException($"Unsupported collection type {propertyInfo.PropertyType} on {propertyInfo}");
 				}
 			}
 			else