Split CPDF_PageObjectHolder off from CPDF_PageObjectList

fpdfsdk/src/fpdf_flatten.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_flatten.h"
 
 #include <algorithm>
 
@@ skipping 24 matching lines @@
   return TRUE;
 }
 
 FX_BOOL GetContentsRect(CPDF_Document* pDoc,
                         CPDF_Dictionary* pDict,
                         CPDF_RectArray* pRectArray) {
   CPDF_Page* pPDFPage = new CPDF_Page;
   pPDFPage->Load(pDoc, pDict, FALSE);
   pPDFPage->ParseContent(nullptr);
 
-  FX_POSITION pos = pPDFPage->GetFirstObjectPosition();
+  FX_POSITION pos = pPDFPage->GetPageObjectList()->GetHeadPosition();
   while (pos) {
-    CPDF_PageObject* pPageObject = pPDFPage->GetNextObject(pos);
+    CPDF_PageObject* pPageObject =
+        pPDFPage->GetPageObjectList()->GetNextObject(pos);
     if (!pPageObject)
       continue;
 
     CPDF_Rect rc;
     rc.left = pPageObject->m_Left;
     rc.right = pPageObject->m_Right;
     rc.bottom = pPageObject->m_Bottom;
     rc.top = pPageObject->m_Top;
 
     if (IsValiableRect(rc, pDict->GetRectBy("MediaBox"))) {
@@ skipping 455 matching lines @@
     pNewXObject->SetData((const uint8_t*)sStream, sStream.GetLength(), FALSE,
                          FALSE);
   }
   pPageDict->RemoveAt("Annots");
 
   ObjectArray.RemoveAll();
   RectArray.RemoveAll();
 
   return FLATTEN_SUCCESS;
 }