Removes unnecessary function in WmWindow

ash/wm/aura/wm_window_aura.h

 // Copyright 2016 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_AURA_WM_WINDOW_AURA_H_
 #define ASH_WM_AURA_WM_WINDOW_AURA_H_
 
 #include "ash/ash_export.h"
 #include "ash/wm/common/wm_window.h"
 #include "base/macros.h"
@@ skipping 72 matching lines @@
   void SetBoundsDirectAnimated(const gfx::Rect& bounds) override;
   void SetBoundsDirectCrossFade(const gfx::Rect& bounds) override;
   void SetBoundsInScreen(const gfx::Rect& bounds_in_screen,
                          const display::Display& dst_display) override;
   gfx::Rect GetBoundsInScreen() const override;
   const gfx::Rect& GetBounds() const override;
   gfx::Rect GetTargetBounds() override;
   void ClearRestoreBounds() override;
   void SetRestoreBoundsInScreen(const gfx::Rect& bounds) override;
   gfx::Rect GetRestoreBoundsInScreen() const override;
-  void OnWMEvent(const wm::WMEvent* event) override;
   bool Contains(const WmWindow* other) const override;
   void SetShowState(ui::WindowShowState show_state) override;
   ui::WindowShowState GetShowState() const override;
   void SetRestoreShowState(ui::WindowShowState show_state) override;
   void SetLockedToRoot(bool value) override;
   void SetCapture() override;
   bool HasCapture() override;
   void ReleaseCapture() override;
   bool HasRestoreBounds() const override;
   bool CanMaximize() const override;
@@ skipping 38 matching lines @@
 
   base::ObserverList<WmWindowObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(WmWindowAura);
 };
 
 }  // namespace wm
 }  // namespace ash
 
 #endif  // ASH_WM_AURA_WM_WINDOW_AURA_H_