Invalidate IPWL_FocusHandler and IPWL_Provider on destruction.

fpdfsdk/include/pdfwindow/PWL_Wnd.h

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef FPDFSDK_INCLUDE_PDFWINDOW_PWL_WND_H_
 #define FPDFSDK_INCLUDE_PDFWINDOW_PWL_WND_H_
 
 #include "core/include/fpdfdoc/fpdf_doc.h"
@@ skipping 270 matching lines @@
 
 class CPWL_Wnd : public CPWL_TimerHandler {
   friend class CPWL_MsgControl;
 
  public:
   CPWL_Wnd();
   ~CPWL_Wnd() override;
 
   void Create(const PWL_CREATEPARAM& cp);
   virtual CFX_ByteString GetClassName() const;
+  void InvalidateFocusHandler(IPWL_FocusHandler* handler);
+  void InvalidateProvider(IPWL_Provider* provider);
   void Destroy();
   void Move(const CPDF_Rect& rcNew, FX_BOOL bReset, FX_BOOL bRefresh);
   virtual void InvalidateRect(CPDF_Rect* pRect = NULL);
 
   void GetAppearanceStream(CFX_ByteString& sAppStream);
   void DrawAppearance(CFX_RenderDevice* pDevice, CFX_Matrix* pUser2Device);
 
   virtual FX_BOOL OnKeyDown(FX_WORD nChar, FX_DWORD nFlag);
   virtual FX_BOOL OnKeyUp(FX_WORD nChar, FX_DWORD nFlag);
   virtual FX_BOOL OnChar(FX_WORD nChar, FX_DWORD nFlag);
@@ skipping 166 matching lines @@
   CPDF_Rect m_rcWindow;
   CPDF_Rect m_rcClip;
 
   FX_BOOL m_bCreated;
   FX_BOOL m_bVisible;
   FX_BOOL m_bNotifying;
   FX_BOOL m_bEnabled;
 };
 
 #endif  // FPDFSDK_INCLUDE_PDFWINDOW_PWL_WND_H_