Relanding the EventTarget fixes for Aura (Ash) as the previous attempt was reverted due to interact…

ash/shell.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ASH_SHELL_H_
 #define ASH_SHELL_H_
 
 #include <utility>
 #include <vector>
 
 #include "ash/ash_export.h"
 #include "ash/system/user/login_status.h"
 #include "ash/wm/cursor_manager.h"
 #include "ash/wm/shelf_types.h"
 #include "ash/wm/system_modal_container_event_filter_delegate.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #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"
 
 class CommandLine;
 
 namespace aura {
 class EventFilter;
 class FocusManager;
 class RootWindow;
@@ skipping 76 matching lines @@
 class VisibilityController;
 class WindowModalityController;
 class WorkspaceController;
 }
 
 // Shell is a singleton object that presents the Shell API and implements the
 // RootWindow's delegate interface.
 //
 // 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;
 
   enum Direction {
     FORWARD,
     BACKWARD
   };
 
   // Accesses private data from a Shell for testing.
@@ skipping 289 matching lines @@
   void InitRootWindowController(internal::RootWindowController* root);
 
   // Initializes the layout managers and event filters specific for
   // primary display.
   void InitLayoutManagersForPrimaryDisplay(
       internal::RootWindowController* root_window_controller);
 
   // ash::internal::SystemModalContainerEventFilterDelegate overrides:
   virtual bool CanWindowReceiveEvents(aura::Window* window) OVERRIDE;
 
+  // Overridden from ui::EventTarget:
+  virtual bool CanAcceptEvents() OVERRIDE;
+  virtual EventTarget* GetParentTarget() OVERRIDE;
+
   static Shell* instance_;
 
   // If set before the Shell is initialized, the mouse cursor will be hidden
   // when the screen is initially created.
   static bool initially_hide_cursor_;
 
   ScreenAsh* screen_;
 
   // Active root window. Never becomes NULL during the session.
   aura::RootWindow* active_root_window_;
@@ skipping 79 matching lines @@
 
   // For testing only: simulate that a modal window is open
   bool simulate_modal_window_open_for_testing_;
 
   DISALLOW_COPY_AND_ASSIGN(Shell);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELL_H_