Fix all the code which has duplicate variable declarations

fpdfsdk/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 464 matching lines @@
     }
 
     CPDF_Dictionary* pXObject = pNewXORes->GetDictBy("XObject");
     if (!pXObject) {
       pXObject = new CPDF_Dictionary;
       pNewXORes->SetAt("XObject", pXObject);
     }
 
     CFX_ByteString sFormName;
     sFormName.Format("F%d", i);
-    uint32_t dwObjNum = pDocument->AddIndirectObject(pObj);
-    pXObject->SetAtReference(sFormName, pDocument, dwObjNum);
+    uint32_t dwStreamObjNum = pDocument->AddIndirectObject(pObj);
+    pXObject->SetAtReference(sFormName, pDocument, dwStreamObjNum);
 
     CPDF_StreamAcc acc;
     acc.LoadAllData(pNewXObject);
 
     const uint8_t* pData = acc.GetData();
     CFX_ByteString sStream(pData, acc.GetSize());
     CFX_ByteString sTemp;
 
     if (matrix.IsIdentity()) {
       matrix.a = 1.0f;
@@ skipping 10 matching lines @@
     sStream += sTemp;
     pNewXObject->SetData(sStream.raw_str(), sStream.GetLength(), FALSE, FALSE);
   }
   pPageDict->RemoveAt("Annots");
 
   ObjectArray.RemoveAll();
   RectArray.RemoveAll();
 
   return FLATTEN_SUCCESS;
 }