Make Chrome limp briefly before freaking out with aura no ash.

ui/aura/desktop/desktop_stacking_client.h

Index: ui/aura/desktop/desktop_stacking_client.h
===================================================================
--- ui/aura/desktop/desktop_stacking_client.h	(revision 137506)
+++ ui/aura/desktop/desktop_stacking_client.h	(working copy)
@@ -9,9 +9,11 @@
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
+#include "base/memory/scoped_ptr.h"
 #include "ui/aura/aura_export.h"
 
 namespace aura {
+class RootWindow;
 class Window;
 
 // A stacking client for the desktop; always sets the default parent to the
@@ -24,6 +26,10 @@
   // Overridden from client::StackingClient:
   virtual Window* GetDefaultParent(Window* window) OVERRIDE;
 
+ private:
+  // Windows with NULL parents are parented to this.
+  scoped_ptr<aura::RootWindow> null_parent_;
+
   DISALLOW_COPY_AND_ASSIGN(DesktopStackingClient);
 };