Watch destruction of widgets around OnAAction() method

fpdfsdk/include/cpdfsdk_pageview.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_PAGEVIEW_H_
 #define FPDFSDK_INCLUDE_CPDFSDK_PAGEVIEW_H_
 
 #include <memory>
 #include <vector>
 
 #include "core/fpdfapi/fpdf_page/include/cpdf_page.h"
 #include "core/fxcrt/include/fx_system.h"
+#include "fpdfsdk/include/cpdfsdk_annot.h"
 #include "fpdfsdk/include/cpdfsdk_document.h"
 
 class CFX_RenderDevice;
 class CPDF_AnnotList;
 class CPDF_RenderOptions;
 
 class CPDFSDK_PageView final : public CPDF_Page::View {
  public:
   CPDFSDK_PageView(CPDFSDK_Document* pSDKDoc, UnderlyingPageType* page);
   ~CPDFSDK_PageView();
 
 #ifdef PDF_ENABLE_XFA
   void PageView_OnDraw(CFX_RenderDevice* pDevice,
                        CFX_Matrix* pUser2Device,
                        CPDF_RenderOptions* pOptions,
                        const FX_RECT& pClip);
 #else   // PDF_ENABLE_XFA
   void PageView_OnDraw(CFX_RenderDevice* pDevice,
                        CFX_Matrix* pUser2Device,
                        CPDF_RenderOptions* pOptions);
 #endif  // PDF_ENABLE_XFA
 
   const CPDF_Annot* GetPDFAnnotAtPoint(FX_FLOAT pageX, FX_FLOAT pageY);
   CPDFSDK_Annot* GetFXAnnotAtPoint(FX_FLOAT pageX, FX_FLOAT pageY);
   const CPDF_Annot* GetPDFWidgetAtPoint(FX_FLOAT pageX, FX_FLOAT pageY);
   CPDFSDK_Annot* GetFXWidgetAtPoint(FX_FLOAT pageX, FX_FLOAT pageY);
   CPDFSDK_Annot* GetFocusAnnot();
-  void SetFocusAnnot(CPDFSDK_Annot* pSDKAnnot, uint32_t nFlag = 0) {
+  void SetFocusAnnot(CPDFSDK_Annot::ObservedPtr* pSDKAnnot,
+                     uint32_t nFlag = 0) {
     m_pSDKDoc->SetFocusAnnot(pSDKAnnot, nFlag);
   }
   FX_BOOL KillFocusAnnot(uint32_t nFlag = 0) {
     return m_pSDKDoc->KillFocusAnnot(nFlag);
   }
   void KillFocusAnnotIfNeeded();
 
   CPDFSDK_Annot* AddAnnot(CPDF_Dictionary* pDict);
   CPDFSDK_Annot* AddAnnot(const FX_CHAR* lpSubType, CPDF_Dictionary* pDict);
   CPDFSDK_Annot* AddAnnot(CPDF_Annot* pPDFAnnot);
@@ skipping 48 matching lines @@
 #endif  // PDF_ENABLE_XFA
 
  private:
   int GetPageIndexForStaticPDF() const;
 
   CFX_Matrix m_curMatrix;
   UnderlyingPageType* const m_page;
   std::unique_ptr<CPDF_AnnotList> m_pAnnotList;
   std::vector<CPDFSDK_Annot*> m_fxAnnotArray;
   CPDFSDK_Document* const m_pSDKDoc;
-  CPDFSDK_Annot* m_CaptureWidget;
+  CPDFSDK_Annot::ObservedPtr m_pCaptureWidget;
 #ifndef PDF_ENABLE_XFA
   bool m_bOwnsPage;
 #endif  // PDF_ENABLE_XFA
   FX_BOOL m_bEnterWidget;
   FX_BOOL m_bExitWidget;
   FX_BOOL m_bOnWidget;
   FX_BOOL m_bValid;
   FX_BOOL m_bLocked;
 };
 
 #endif  // FPDFSDK_INCLUDE_CPDFSDK_PAGEVIEW_H_