Fix a crashier in CPDFSDK_Document::GetPageView()

fpdfsdk/src/fpdfxfa/fpdfxfa_doc.cpp

 // 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
 
 #include "fpdfsdk/include/fsdk_define.h"
 #include "fpdfsdk/include/fpdfxfa/fpdfxfa_doc.h"
 #include "fpdfsdk/include/fsdk_mgr.h"
 #include "fpdfsdk/include/fpdfxfa/fpdfxfa_app.h"
@@ skipping 27 matching lines @@
     : m_iDocType(DOCTYPE_PDF),
       m_pPDFDoc(pPDFDoc),
       m_pSDKDoc(nullptr),
       m_pXFADoc(nullptr),
       m_pXFADocView(nullptr),
       m_pApp(pProvider),
       m_pJSContext(nullptr) {
 }
 
 CPDFXFA_Document::~CPDFXFA_Document() {
-  if (m_pJSContext && m_pSDKDoc && m_pSDKDoc->GetEnv())
-    m_pSDKDoc->GetEnv()->GetJSRuntime()->ReleaseContext(m_pJSContext);
-
-  delete m_pSDKDoc;
-
-  if (m_pPDFDoc) {
-    CPDF_Parser* pParser = m_pPDFDoc->GetParser();
-    if (pParser)
-      delete pParser;
-    else
-      delete m_pPDFDoc;
-  }
   if (m_pXFADoc) {
     IXFA_App* pApp = m_pApp->GetXFAApp();
     if (pApp) {
       IXFA_DocHandler* pDocHandler = pApp->GetDocHandler();
       if (pDocHandler) {
         CloseXFADoc(pDocHandler);
       }
     }
     delete m_pXFADoc;
   }
+  if (m_pJSContext && m_pSDKDoc && m_pSDKDoc->GetEnv())
+    m_pSDKDoc->GetEnv()->GetJSRuntime()->ReleaseContext(m_pJSContext);
+  delete m_pSDKDoc;
+  if (m_pPDFDoc) {
+    CPDF_Parser* pParser = m_pPDFDoc->GetParser();
+    if (pParser)
+      delete pParser;
+    else
+      delete m_pPDFDoc;
+  }
 }
 
 FX_BOOL CPDFXFA_Document::LoadXFADoc() {
   if (!m_pPDFDoc)
     return FALSE;
 
   m_XFAPageList.RemoveAll();
 
   IXFA_App* pApp = m_pApp->GetXFAApp();
   if (!pApp)
@@ skipping 403 matching lines @@
     pPage = GetPage(nPageIndex);
     if (pPage)
       pPage->SetXFAPageView(pPageView);
     pEnv->FFI_PageEvent(nPageIndex, dwFlags);
     return;
   }
   pPage = GetPage(pPageView);
   if (!pPage)
     return;
   pEnv->FFI_PageEvent(pPage->GetPageIndex(), dwFlags);
-  m_pSDKDoc->GetPageView(pPage)->ClearFXAnnots();

[jun_fang, 2016/02/04 06:15:10]

When a XFA page is deleted, it doesn't need to clear annotations
on this page.
That's because a XFA page is dynamically created by layout process. 
A XFA page is a virtual and dynamic page. Annotations will be mapped
to a new XFA page during performing layout. 

   pPage->Release();
 }
 
 void CPDFXFA_Document::WidgetEvent(IXFA_Widget* hWidget,
                                    CXFA_WidgetAcc* pWidgetData,
                                    FX_DWORD dwEvent,
                                    void* pParam,
                                    void* pAdditional) {
   if (m_iDocType != DOCTYPE_DYNAMIC_XFA || !hWidget)
     return;
@@ skipping 748 matching lines @@
   }
 
   return _GetHValueByName(szPropName, hValue,
                           m_pSDKDoc->GetEnv()->GetJSRuntime());
 }
 FX_BOOL CPDFXFA_Document::_GetHValueByName(const CFX_ByteStringC& utf8Name,
                                            FXJSE_HVALUE hValue,
                                            IJS_Runtime* runTime) {
   return runTime->GetHValueByName(utf8Name, hValue);
 }