Fix #2610: Explicitly qualify members in TemplateBindings.

At a later point, we can add some more logic that tries to infer the target type of the binding and applies simplification accordingly.

ILSpy.BamlDecompiler.Tests/Cases/AvalonDockCommon.xaml

@@ -21,7 +21,7 @@
 		<Setter Property="Template">
 			<Setter.Value>
 				<ControlTemplate TargetType="{x:Type ad:Resizer}">
-					<Border Background="{TemplateBinding Background}" />
+					<Border Background="{TemplateBinding Control.Background}" />
 				</ControlTemplate>
 			</Setter.Value>
 		</Setter>

ILSpy.BamlDecompiler/Handlers/Records/PropertyWithExtensionHandler.cs

@@ -59,7 +59,7 @@ namespace ILSpy.BamlDecompiler.Handlers
 				var value = ctx.ResolveProperty(record.ValueId);
 
 				value.DeclaringType.ResolveNamespace(parent.Xaml, ctx);
-				var xName = value.ToXName(ctx, parent.Xaml, false);
+				var xName = value.ToXName(ctx, parent.Xaml, true);
 
 				ext.Initializer = new object[] { ctx.ToString(parent.Xaml, xName) };
 			}