Removed bogus test.

It wasn't testing the actual leak and relied on messy reflection so
removing it.

tests/Perspex.LeakTests/ControlTests.cs

@@ -257,55 +257,6 @@ namespace Perspex.LeakTests
             }
         }
 
-        [Fact]
-        public void Class_Listener_Is_Freed()
-        {
-            using (UnitTestApplication.Start(TestServices.StyledWindow))
-            {
-                Func<Window> run = () =>
-                {
-                    var window = new Window
-                    {
-                        Styles = new Styles
-                        {
-                            new Style(x => x.OfType<Border>().Class("foo"))
-                            {
-                                Setters = new[]
-                                {
-                                    new Setter(Border.BorderThicknessProperty, 1),
-                                }
-                            }
-                        },
-                        Content = new Border
-                        {
-                            Classes = new Classes("foo"),
-                        }
-                    };
-
-                    // Do a layout and make sure that TreeViewItems get realized.
-                    LayoutManager.Instance.ExecuteInitialLayoutPass(window);
-                    Assert.Equal(1, ((Border)window.Content).BorderThickness);
-
-                    // Clear the content and ensure the TreeView is removed.
-                    window.Content = null;
-                    LayoutManager.Instance.ExecuteLayoutPass();
-                    Assert.Null(window.Presenter.Child);
-
-                    return window;
-                };
-
-                var result = run();
-
-                var type = Type.GetType(
-                    "System.Reactive.Linq.ObservableImpl.FromEventPattern+Impl`2[[System.Collections.Specialized.NotifyCollectionChangedEventHandler, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[System.Collections.Specialized.NotifyCollectionChangedEventArgs, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]], System.Reactive.Linq, Version=2.2.5.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35");
-
-                Assert.NotNull(type);
-
-                dotMemory.Check(memory =>
-                    Assert.Equal(0, memory.GetObjects(where => where.Type.Is(type)).ObjectsCount));
-            }
-        }
-
         private class TestTemplatedControl : TemplatedControl
         {
             public static readonly StyledProperty<int> IsCanvasVisibleProperty =