Fix a few more warnings in chromium_code mode.

core/src/fpdfapi/fpdf_page/fpdf_page_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 "../../../include/fpdfapi/fpdf_page.h"
 #include "../../../include/fpdfapi/fpdf_module.h"
 #include "../../../include/fdrm/fx_crypt.h"
 #include "../fpdf_font/font_int.h"
@@ skipping 128 matching lines @@
     m_ColorSpaceMap.InitHashTable(32);
     m_PatternMap.InitHashTable(16);
     m_ImageMap.InitHashTable(64);
     m_IccProfileMap.InitHashTable(16);
     m_FontFileMap.InitHashTable(32);
 }
 CPDF_DocPageData::~CPDF_DocPageData()
 {
     Clear(FALSE);
     Clear(TRUE);
-    FX_POSITION pos = NULL;
 }
 void CPDF_DocPageData::Clear(FX_BOOL bRelease)
 {
     FX_POSITION pos;
     FX_DWORD    nCount;
     {
         pos = m_PatternMap.GetStartPosition();
         while (pos) {
             CPDF_Object* ptObj;
             CPDF_CountedObject<CPDF_Pattern*>* ptData;
@@ skipping 478 matching lines @@
     m_FontFileMap.SetAt(pFontStream, ftData);
     return pFontFile;
 }
 void CPDF_DocPageData::ReleaseFontFileStreamAcc(CPDF_Stream* pFontStream, FX_BOOL bForce)
 {
     if (!pFontStream) {
         return;
     }
     PDF_DocPageData_Release<CPDF_Stream*, CPDF_StreamAcc*>(m_FontFileMap, pFontStream, NULL, bForce);
 }