Merge branch '1733-cleaning-up-theme-resources' of https://github.com/wdcossey/Avalonia into 1733-cleaning-up-theme-resources

scripts/ReplaceNugetCache.ps1

@@ -1,5 +1,6 @@
+copy ..\samples\ControlCatalog.Desktop\bin\Debug\net461\Avalonia**.dll ~\.nuget\packages\avalonia\$args\lib\net461\
 copy ..\samples\ControlCatalog.NetCore\bin\Debug\netcoreapp2.0\Avalonia**.dll ~\.nuget\packages\avalonia\$args\lib\netcoreapp2.0\
-copy ..\samples\ControlCatalog.NetCore.\bin\Debug\netcoreapp2.0\Avalonia**.dll ~\.nuget\packages\avalonia\$args\lib\netstandard2.0\
-copy ..\samples\ControlCatalog.NetCore.\bin\Debug\netcoreapp2.0\Avalonia**.dll ~\.nuget\packages\avalonia.gtk3\$args\lib\netstandard2.0\
-copy ..\samples\ControlCatalog.NetCore.\bin\Debug\netcoreapp2.0\Avalonia**.dll ~\.nuget\packages\avalonia.win32\$args\lib\netstandard2.0\
-copy ..\samples\ControlCatalog.NetCore.\bin\Debug\netcoreapp2.0\Avalonia**.dll ~\.nuget\packages\avalonia.skia\$args\lib\netstandard2.0\
+copy ..\samples\ControlCatalog.NetCore\bin\Debug\netcoreapp2.0\Avalonia**.dll ~\.nuget\packages\avalonia\$args\lib\netstandard2.0\
+copy ..\samples\ControlCatalog.NetCore\bin\Debug\netcoreapp2.0\Avalonia.Gtk3.dll ~\.nuget\packages\avalonia.gtk3\$args\lib\netstandard2.0\
+copy ..\samples\ControlCatalog.NetCore\bin\Debug\netcoreapp2.0\Avalonia.Win32.dll ~\.nuget\packages\avalonia.win32\$args\lib\netstandard2.0\
+copy ..\samples\ControlCatalog.NetCore\bin\Debug\netcoreapp2.0\Avalonia.Skia.dll ~\.nuget\packages\avalonia.skia\$args\lib\netstandard2.0\

src/Markup/Avalonia.Markup/Data/Binding.cs

@@ -150,7 +150,9 @@ namespace Avalonia.Data
             }
             else if (RelativeSource.Mode == RelativeSourceMode.Self)
             {
-                observer = CreateSourceObserver(target, node);
+                observer = CreateSourceObserver(
+                    (target as IStyledElement) ?? (anchor as IStyledElement),
+                    node);
             }
             else if (RelativeSource.Mode == RelativeSourceMode.TemplatedParent)
             {