Fix regression bug with application title no longer grayed out. (#632)

Move back the VisualStateManager node to the root XAML element to fix visual states of the titlebar.

### How changes were validated:
- Manually

Fixes #631

src/Calculator/Views/TitleBar.xaml

@@ -11,9 +11,6 @@
     <Grid x:Name="LayoutRoot"
           Height="32"
           HorizontalAlignment="Stretch">
-        <Grid x:Name="BackgroundElement"
-              Background="Transparent"
-              Height="32">
         <VisualStateManager.VisualStateGroups>
             <VisualStateGroup x:Name="WindowFocusStates">
                 <VisualState x:Name="WindowFocused"/>
@@ -24,6 +21,9 @@
                 </VisualState>
             </VisualStateGroup>
         </VisualStateManager.VisualStateGroups>
+        <Grid x:Name="BackgroundElement"
+              Background="Transparent"
+              Height="32">
             <TextBlock x:Name="AppName"
                    x:Uid="AppName"
                    Margin="12,0,12,0"