Fix a few windows compile warnings

core/src/fpdftext/fpdf_text_int.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_resource.h"
 #include "../../include/fpdfapi/fpdf_pageobj.h"
 #include "../../include/fpdftext/fpdf_text.h"
 #include "../../include/fpdfapi/fpdf_page.h"
@@ skipping 1869 matching lines @@
         FX_INT32 i, j;
         i = iCharListStartAppend;
         j = m_TempCharList.GetSize() - 1;
         for (; i < j; i++, j--) {
             std::swap(m_TempCharList[i], m_TempCharList[j]);
             std::swap(m_TempCharList[i].m_Index, m_TempCharList[j].m_Index);
         }
         FX_WCHAR * pTempBuffer = m_TempTextBuf.GetBuffer();
         i = iBufStartAppend;
         j = m_TempTextBuf.GetLength() - 1;
-        FX_WCHAR wTemp;
         for (; i < j; i++, j--) {
             std::swap(pTempBuffer[i], pTempBuffer[j]);
         }
     }
 }
 FX_INT32 CPDF_TextPage::GetTextObjectWritingMode(const CPDF_TextObject* pTextObj)
 {
     FX_INT32 nChars = pTextObj->CountChars();
     if (nChars == 1) {
         return m_TextlineDir;
@@ skipping 939 matching lines @@
     if (!m_IsParserd || index < 0 || index >= m_LinkList.GetSize()) {
         return;
     }
     CPDF_LinkExt* link = NULL;
     link = m_LinkList.GetAt(index);
     if (!link) {
         return ;
     }
     m_pTextPage->GetRectArray(link->m_Start, link->m_Count, rects);
 }