chromeos: Move files in //ash/common to //ash, part 3

ash/wm/overlay_event_filter.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_WM_OVERLAY_EVENT_FILTER_H_
 #define ASH_WM_OVERLAY_EVENT_FILTER_H_
 
 #include "ash/ash_export.h"
-#include "ash/common/shell_observer.h"
+#include "ash/shell_observer.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "ui/aura/window.h"
 #include "ui/events/event_handler.h"
 
 namespace ash {
 
 // EventFilter for the "overlay window", which intercepts events before they are
 // processed by the usual path (e.g. the partial screenshot UI, the keyboard
 // overlay).  It does nothing the first time, but works when |Activate()| is
@@ skipping 45 matching lines @@
 
  private:
   Delegate* delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(OverlayEventFilter);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_OVERLAY_EVENT_FILTER_H_