Register a separate default ui::EventTarget for Aura (Ash) to ensure that it does not interfere wit…

ash/shell.h

Index: ash/shell.h
===================================================================
--- ash/shell.h	(revision 163961)
+++ ash/shell.h	(working copy)
@@ -18,6 +18,7 @@
 #include "base/gtest_prod_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/observer_list.h"
+#include "ui/base/events/event_target.h"
 #include "ui/gfx/insets.h"
 #include "ui/gfx/screen.h"
 #include "ui/gfx/size.h"
@@ -115,7 +116,8 @@
 //
 // Upon creation, the Shell sets itself as the RootWindow's delegate, which
 // takes ownership of the Shell.
-class ASH_EXPORT Shell : internal::SystemModalContainerEventFilterDelegate{
+class ASH_EXPORT Shell : internal::SystemModalContainerEventFilterDelegate,
+                         public ui::EventTarget {
  public:
   typedef std::vector<aura::RootWindow*> RootWindowList;
   typedef std::vector<internal::RootWindowController*> RootWindowControllerList;
@@ -192,6 +194,10 @@
     active_root_window_ = active_root_window;
   }
 
+  // Overridden from ui::EventTarget:
+  virtual bool CanAcceptEvents() OVERRIDE;
+  virtual EventTarget* GetParentTarget() OVERRIDE;
+
   // Adds or removes |filter| from the aura::Env's pre-target event-handler
   // list.
   void AddEnvEventFilter(aura::EventFilter* filter);