Don't validate thread affinity for bindings.

The scheduler should ensure that bindings are called on the correct
thread.

src/Avalonia.Base/AvaloniaObject.cs

@@ -335,7 +335,6 @@ namespace Avalonia
                 }
 
                 subscription = source
-                    .Do(_ => VerifyAccess())
                     .Select(x => CastOrDefault(x, property.PropertyType))
                     .Do(_ => { }, () => _directBindings.Remove(subscription))
                     .Subscribe(x => SetDirectValue(property, x));

tests/Avalonia.Base.UnitTests/AvaloniaObjectTests_Threading.cs

@@ -49,23 +49,6 @@ namespace Avalonia.Base.UnitTests
             }
         }
 
-        [Fact]
-        public void StyledProperty_Binding_Producing_Value_Should_Throw()
-        {
-            var ti = new ThreadingInterface(true);
-            using (UnitTestApplication.Start(new TestServices(threadingInterface: ti)))
-            {
-                var target = new Class1();
-
-                var source = new BehaviorSubject<string>("foo");
-
-                target.Bind(Class1.StyledProperty, source);
-
-                ti.CurrentThreadIsLoopThread = false;
-                Assert.Throws<InvalidOperationException>(() => source.OnNext("bar"));
-            }
-        }
-
         [Fact]
         public void StyledProperty_ClearValue_Should_Throw()
         {
@@ -124,23 +107,6 @@ namespace Avalonia.Base.UnitTests
             }
         }
 
-        [Fact]
-        public void DirectProperty_Binding_Producing_Value_Should_Throw()
-        {
-            var ti = new ThreadingInterface(true);
-            using (UnitTestApplication.Start(new TestServices(threadingInterface: ti)))
-            {
-                var target = new Class1();
-
-                var source = new BehaviorSubject<string>("foo");
-
-                target.Bind(Class1.DirectProperty, source);
-
-                ti.CurrentThreadIsLoopThread = false;
-                Assert.Throws<InvalidOperationException>(() => source.OnNext("bar"));
-            }
-        }
-
         [Fact]
         public void DirectProperty_ClearValue_Should_Throw()
         {