Added test that fails after resource refactor.

`Changing_Resource_In_Templated_Parent_Should_Affect_Templated_Child` now fails because resource changed messages no longer traverse into templated children.

tests/Avalonia.Controls.UnitTests/Primitives/TemplatedControlTests.cs

@@ -10,6 +10,7 @@ using Avalonia.Styling;
 using Avalonia.UnitTests;
 using Avalonia.VisualTree;
 using Xunit;
+using Avalonia.Media;
 
 namespace Avalonia.Controls.UnitTests.Primitives
 {
@@ -512,6 +513,68 @@ namespace Avalonia.Controls.UnitTests.Primitives
             }
         }
 
+        [Fact]
+        public void Templated_Child_Should_Find_Resource_In_TemplatedParent()
+        {
+            var target = new ContentControl
+            {
+                Resources =
+                {
+                    { "red", Brushes.Red },
+                },
+                Template = new FuncControlTemplate<ContentControl>((x, scope) =>
+                {
+                    var result = new ContentPresenter
+                    {
+                        Name = "PART_ContentPresenter",
+                        [!ContentPresenter.ContentProperty] = x[!ContentControl.ContentProperty],
+                    }.RegisterInNameScope(scope);
+
+                    result.Bind(ContentPresenter.BackgroundProperty, result.GetResourceObservable("red"));
+
+                    return result;
+                }),
+            };
+
+            target.ApplyTemplate();
+
+            var contentPresenter = Assert.IsType<ContentPresenter>(target.GetVisualChildren().Single());
+            Assert.Same(Brushes.Red, contentPresenter.Background);
+        }
+
+        [Fact]
+        public void Changing_Resource_In_Templated_Parent_Should_Affect_Templated_Child()
+        {
+            var target = new ContentControl
+            {
+                Resources =
+                {
+                    { "red", Brushes.Red },
+                },
+                Template = new FuncControlTemplate<ContentControl>((x, scope) =>
+                {
+                    var result = new ContentPresenter
+                    {
+                        Name = "PART_ContentPresenter",
+                        [!ContentPresenter.ContentProperty] = x[!ContentControl.ContentProperty],
+                    }.RegisterInNameScope(scope);
+
+                    result.Bind(ContentPresenter.BackgroundProperty, result.GetResourceObservable("red"));
+
+                    return result;
+                }),
+            };
+
+            target.ApplyTemplate();
+
+            var contentPresenter = Assert.IsType<ContentPresenter>(target.GetVisualChildren().Single());
+            Assert.Same(Brushes.Red, contentPresenter.Background);
+
+            target.Resources["red"] = Brushes.Green;
+
+            Assert.Same(Brushes.Green, contentPresenter.Background);
+        }
+
         private static IControl ScrollingContentControlTemplate(ContentControl control, INameScope scope)
         {
             return new Border