Fix use after free when handling async touch events

ui/views/widget/native_widget_win.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 UI_VIEWS_WIDGET_NATIVE_WIDGET_WIN_H_
 #define UI_VIEWS_WIDGET_NATIVE_WIDGET_WIN_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 193 matching lines @@
   virtual void HandleWorkAreaChanged() OVERRIDE;
   virtual void HandleVisibilityChanging(bool visible) OVERRIDE;
   virtual void HandleVisibilityChanged(bool visible) OVERRIDE;
   virtual void HandleClientSizeChanged(const gfx::Size& new_size) OVERRIDE;
   virtual void HandleFrameChanged() OVERRIDE;
   virtual void HandleNativeFocus(HWND last_focused_window) OVERRIDE;
   virtual void HandleNativeBlur(HWND focused_window) OVERRIDE;
   virtual bool HandleMouseEvent(const ui::MouseEvent& event) OVERRIDE;
   virtual bool HandleKeyEvent(const ui::KeyEvent& event) OVERRIDE;
   virtual bool HandleUntranslatedKeyEvent(const ui::KeyEvent& event) OVERRIDE;
-  virtual bool HandleTouchEvent(const ui::TouchEvent& event) OVERRIDE;
+  virtual void HandleTouchEvent(const ui::TouchEvent& event) OVERRIDE;
   virtual bool HandleIMEMessage(UINT message,
                                 WPARAM w_param,
                                 LPARAM l_param,
                                 LRESULT* result) OVERRIDE;
   virtual void HandleInputLanguageChange(DWORD character_set,
                                          HKL input_language_id) OVERRIDE;
   virtual bool HandlePaintAccelerated(const gfx::Rect& invalid_rect) OVERRIDE;
   virtual void HandlePaint(gfx::Canvas* canvas) OVERRIDE;
   virtual bool HandleTooltipNotify(int w_param,
                                    NMHDR* l_param,
@@ skipping 41 matching lines @@
   bool has_non_client_view_;
 
   scoped_ptr<HWNDMessageHandler> message_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeWidgetWin);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_NATIVE_WIDGET_WIN_H_