Reorder the NativeViews attached to a view via kViewHostKey according to the position of the view

ui/views/widget/native_widget_aura.h

Index: ui/views/widget/native_widget_aura.h
diff --git a/ui/views/widget/native_widget_aura.h b/ui/views/widget/native_widget_aura.h
index c7991115e223181ea6d1adb78443aa9f4f06bcfb..24e0cee06941175f6e80a1b229a64d0d96481e5b 100644
--- a/ui/views/widget/native_widget_aura.h
+++ b/ui/views/widget/native_widget_aura.h
@@ -28,6 +28,7 @@ namespace views {
 
 class DropHelper;
 class NativeWidgetAuraWindowObserver;
+class NativeWidgetLayerReordererAura;
 class TooltipManagerAura;
 
 class VIEWS_EXPORT NativeWidgetAura
@@ -59,6 +60,8 @@ class VIEWS_EXPORT NativeWidgetAura
   virtual ui::Compositor* GetCompositor() OVERRIDE;
   virtual gfx::Vector2d CalculateOffsetToAncestorWithLayer(
       ui::Layer** layer_parent) OVERRIDE;
+  virtual void ReorderLayers() OVERRIDE;
+  virtual bool HasNativeViewAttachedToViewTree() const OVERRIDE;
   virtual void ViewRemoved(View* view) OVERRIDE;
   virtual void SetNativeWindowProperty(const char* name, void* value) OVERRIDE;
   virtual void* GetNativeWindowProperty(const char* name) const OVERRIDE;
@@ -206,6 +209,10 @@ class VIEWS_EXPORT NativeWidgetAura
 
   scoped_ptr<TooltipManagerAura> tooltip_manager_;
 
+  // Reorders layers and windows based on the order of views with layers and
+  // views with attached windows in the widget's view hierarchy.
+  scoped_ptr<NativeWidgetLayerReordererAura> layer_reorderer_;
+
   scoped_ptr<NativeWidgetAuraWindowObserver> active_window_observer_;
 
   scoped_ptr<DropHelper> drop_helper_;