Watch destruction of widgets around OnAAction() method

fpdfsdk/include/cpdfsdk_widgethandler.h

 // Copyright 2016 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_CPDFSDK_WIDGETHANDLER_H_
 #define FPDFSDK_INCLUDE_CPDFSDK_WIDGETHANDLER_H_
 
 #include "core/fxcrt/include/fx_basic.h"
@@ skipping 32 matching lines @@
                   const CFX_FloatPoint& point) override;
   void OnDraw(CPDFSDK_PageView* pPageView,
               CPDFSDK_Annot* pAnnot,
               CFX_RenderDevice* pDevice,
               CFX_Matrix* pUser2Device,
               bool bDrawAnnots) override;
   void OnCreate(CPDFSDK_Annot* pAnnot) override;
   void OnLoad(CPDFSDK_Annot* pAnnot) override;
   void OnDelete(CPDFSDK_Annot* pAnnot) override;
   void OnRelease(CPDFSDK_Annot* pAnnot) override;
+
   void OnMouseEnter(CPDFSDK_PageView* pPageView,
-                    CPDFSDK_Annot* pAnnot,
+                    CPDFSDK_Annot::ObservedPtr* pAnnot,
                     uint32_t nFlag) override;
   void OnMouseExit(CPDFSDK_PageView* pPageView,
-                   CPDFSDK_Annot* pAnnot,
+                   CPDFSDK_Annot::ObservedPtr* pAnnot,
                    uint32_t nFlag) override;
   FX_BOOL OnLButtonDown(CPDFSDK_PageView* pPageView,
-                        CPDFSDK_Annot* pAnnot,
+                        CPDFSDK_Annot::ObservedPtr* pAnnot,
                         uint32_t nFlags,
                         const CFX_FloatPoint& point) override;
   FX_BOOL OnLButtonUp(CPDFSDK_PageView* pPageView,
-                      CPDFSDK_Annot* pAnnot,
+                      CPDFSDK_Annot::ObservedPtr* pAnnot,
                       uint32_t nFlags,
                       const CFX_FloatPoint& point) override;
   FX_BOOL OnLButtonDblClk(CPDFSDK_PageView* pPageView,
-                          CPDFSDK_Annot* pAnnot,
+                          CPDFSDK_Annot::ObservedPtr* pAnnot,
                           uint32_t nFlags,
                           const CFX_FloatPoint& point) override;
   FX_BOOL OnMouseMove(CPDFSDK_PageView* pPageView,
-                      CPDFSDK_Annot* pAnnot,
+                      CPDFSDK_Annot::ObservedPtr* pAnnot,
                       uint32_t nFlags,
                       const CFX_FloatPoint& point) override;
   FX_BOOL OnMouseWheel(CPDFSDK_PageView* pPageView,
-                       CPDFSDK_Annot* pAnnot,
+                       CPDFSDK_Annot::ObservedPtr* pAnnot,
                        uint32_t nFlags,
                        short zDelta,
                        const CFX_FloatPoint& point) override;
   FX_BOOL OnRButtonDown(CPDFSDK_PageView* pPageView,
-                        CPDFSDK_Annot* pAnnot,
+                        CPDFSDK_Annot::ObservedPtr* pAnnot,
                         uint32_t nFlags,
                         const CFX_FloatPoint& point) override;
   FX_BOOL OnRButtonUp(CPDFSDK_PageView* pPageView,
-                      CPDFSDK_Annot* pAnnot,
+                      CPDFSDK_Annot::ObservedPtr* pAnnot,
                       uint32_t nFlags,
                       const CFX_FloatPoint& point) override;
   FX_BOOL OnRButtonDblClk(CPDFSDK_PageView* pPageView,
-                          CPDFSDK_Annot* pAnnot,
+                          CPDFSDK_Annot::ObservedPtr* pAnnot,
                           uint32_t nFlags,
                           const CFX_FloatPoint& point) override;
   FX_BOOL OnChar(CPDFSDK_Annot* pAnnot,
                  uint32_t nChar,
                  uint32_t nFlags) override;
   FX_BOOL OnKeyDown(CPDFSDK_Annot* pAnnot, int nKeyCode, int nFlag) override;
   FX_BOOL OnKeyUp(CPDFSDK_Annot* pAnnot, int nKeyCode, int nFlag) override;
   void OnDeSelected(CPDFSDK_Annot* pAnnot) override {}
   void OnSelected(CPDFSDK_Annot* pAnnot) override {}
-  FX_BOOL OnSetFocus(CPDFSDK_Annot* pAnnot, uint32_t nFlag) override;
-  FX_BOOL OnKillFocus(CPDFSDK_Annot* pAnnot, uint32_t nFlag) override;
+  FX_BOOL OnSetFocus(CPDFSDK_Annot::ObservedPtr* pAnnot,
+                     uint32_t nFlag) override;
+  FX_BOOL OnKillFocus(CPDFSDK_Annot::ObservedPtr* pAnnot,
+                      uint32_t nFlag) override;
 #ifdef PDF_ENABLE_XFA
-  FX_BOOL OnXFAChangedFocus(CPDFSDK_Annot* pOldAnnot,
-                            CPDFSDK_Annot* pNewAnnot) override;
+  FX_BOOL OnXFAChangedFocus(CPDFSDK_Annot::ObservedPtr* pOldAnnot,
+                            CPDFSDK_Annot::ObservedPtr* pNewAnnot) override;
 #endif  // PDF_ENABLE_XFA
 
   void SetFormFiller(CFFL_InteractiveFormFiller* pFiller) {
     m_pFormFiller = pFiller;
   }
   CFFL_InteractiveFormFiller* GetFormFiller() { return m_pFormFiller; }
 
  private:
   CPDFSDK_Environment* m_pEnv;
   CFFL_InteractiveFormFiller* m_pFormFiller;
 };
 
 #endif  // FPDFSDK_INCLUDE_CPDFSDK_WIDGETHANDLER_H_