Fix crashing in CPDFXFA_Document::GetPage()

fpdfsdk/include/fpdfxfa/fpdfxfa_page.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 _FPDFXFA_PAGEVIEW_H_
 #define _FPDFXFA_PAGEVIEW_H_
 
 class CPDFXFA_Page {
  public:
   CPDFXFA_Page(CPDFXFA_Document* pDoc, int page_index);
   ~CPDFXFA_Page();
 
   void Release();
   void AddRef() { m_iRef++; }
   FX_BOOL LoadPage();
   FX_BOOL LoadPDFPage(CPDF_Dictionary* pageDict);
   CPDFXFA_Document* GetDocument() { return m_pDocument; }
   int GetPageIndex() { return m_iPageIndex; }
   CPDF_Page* GetPDFPage() { return m_pPDFPage; }
   IXFA_PageView* GetXFAPageView() { return m_pXFAPageView; }
+  void SetXFAPageView(IXFA_PageView* pPageView) { m_pXFAPageView = pPageView; }
 
   FX_FLOAT GetPageWidth();
   FX_FLOAT GetPageHeight();
 
   void DeviceToPage(int start_x,
                     int start_y,
                     int size_x,
                     int size_y,
                     int rotate,
                     int device_x,
@@ skipping 23 matching lines @@
 
  private:
   CPDF_Page* m_pPDFPage;
   IXFA_PageView* m_pXFAPageView;
   int m_iPageIndex;
   CPDFXFA_Document* m_pDocument;
   int m_iRef;
 };
 
 #endif