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

ui/views/widget/widget.cc

Index: ui/views/widget/widget.cc
diff --git a/ui/views/widget/widget.cc b/ui/views/widget/widget.cc
index b61dfaf22346a109fc83678bc0618a5b1cd73c85..90568bd52deee09218afdb9c07833de469f3918f 100644
--- a/ui/views/widget/widget.cc
+++ b/ui/views/widget/widget.cc
@@ -884,6 +884,10 @@ ui::Layer* Widget::GetLayer() {
   return native_widget_->GetLayer();
 }
 
+void Widget::ReorderNativeViews() {
+  native_widget_->ReorderNativeViews();
+}
+
 void Widget::UpdateRootLayers() {
   // Calculate the layers requires traversing the tree, and since nearly any
   // mutation of the tree can trigger this call we delay until absolutely