Missing property changes.

src/Avalonia.Base/DirectPropertyBase.cs

@@ -2,7 +2,6 @@
 using Avalonia.Data;
 using Avalonia.Reactive;
 using Avalonia.Styling;
-using Avalonia.Utilities;
 
 namespace Avalonia
 {
@@ -188,10 +187,10 @@ namespace Avalonia
             }
             else if (value is ITemplate template && !typeof(ITemplate).IsAssignableFrom(PropertyType))
             {
-                return new PropertySetterLazyInstance<TValue>(
+                return new PropertySetterTemplateInstance<TValue>(
                     target,
                     this,
-                    () => (TValue)template.Build());
+                    template);
             }
             else
             {

src/Avalonia.Base/StyledPropertyBase.cs

@@ -1,9 +1,7 @@
 using System;
-using System.Diagnostics;
 using Avalonia.Data;
 using Avalonia.Reactive;
 using Avalonia.Styling;
-using Avalonia.Utilities;
 
 namespace Avalonia
 {
@@ -12,7 +10,7 @@ namespace Avalonia
     /// </summary>
     public abstract class StyledPropertyBase<TValue> : AvaloniaProperty<TValue>, IStyledPropertyAccessor
     {
-        private bool _inherits;
+        private readonly bool _inherits;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="StyledPropertyBase{T}"/> class.
@@ -243,10 +241,10 @@ namespace Avalonia
             }
             else if (value is ITemplate template && !typeof(ITemplate).IsAssignableFrom(PropertyType))
             {
-                return new PropertySetterLazyInstance<TValue>(
+                return new PropertySetterTemplateInstance<TValue>(
                     target,
                     this,
-                    () => (TValue)template.Build());
+                    template);
             }
             else
             {