XFA: add CPDFDocumentToFPDFDocument()

fpdfsdk/src/fpdfeditpage.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 "../../public/fpdf_edit.h"
 #include "../../public/fpdf_formfill.h"
 #include "../include/fsdk_define.h"
 #include "../include/fpdfxfa/fpdfxfa_doc.h"
@@ skipping 25 matching lines @@
   }
 
   CPDF_Dictionary* pInfoDict = NULL;
   pInfoDict = pDoc->GetInfo();
   if (pInfoDict) {
     if (FSDK_IsSandBoxPolicyEnabled(FPDF_POLICY_MACHINETIME_ACCESS))
       pInfoDict->SetAt("CreationDate", new CPDF_String(DateStr));
     pInfoDict->SetAt("Creator", new CPDF_String(L"PDFium"));
   }
 
-  CPDFXFA_App* pApp = CPDFXFA_App::GetInstance();
-  return new CPDFXFA_Document(pDoc, pApp);
+  return FPDFDocumentFromCPDFDocument(pDoc);
 }
 
 DLLEXPORT void STDCALL FPDFPage_Delete(FPDF_DOCUMENT document, int page_index) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc || page_index < 0 || page_index >= pDoc->GetPageCount())
     return;
 
   pDoc->DeletePage(page_index);
 }
 
@@ skipping 112 matching lines @@
       CPDF_FormObject* pFormObj = (CPDF_FormObject*)pPageObj;
       pFormObj->CalcBoundingBox();
       break;
     }
     default:
       break;
   }
 }
 
 DLLEXPORT int STDCALL FPDFPage_CountObject(FPDF_PAGE page) {
-  CPDF_Page* pPage = ((CPDFXFA_Page*)page)->GetPDFPage();
+  CPDF_Page* pPage = CPDFPageFromFPDFPage(page);
   if (!pPage || !pPage->m_pFormDict || !pPage->m_pFormDict->KeyExist("Type") ||
       !pPage->m_pFormDict->GetElement("Type")->GetDirect() ||
       pPage->m_pFormDict->GetElement("Type")->GetDirect()->GetString().Compare(
           "Page")) {
     return -1;
   }
   return pPage->CountObjects();
 }
 
 DLLEXPORT FPDF_PAGEOBJECT STDCALL FPDFPage_GetObject(FPDF_PAGE page,
@@ skipping 119 matching lines @@
       !pPage->m_pFormDict->GetElement("Type")->GetDirect() ||
       pPage->m_pFormDict->GetElement("Type")->GetDirect()->GetString().Compare(
           "Page")) {
     return;
   }
   CPDF_Dictionary* pDict = pPage->m_pFormDict;
   rotate %= 4;
 
   pDict->SetAt("Rotate", new CPDF_Number(rotate * 90));
 }