Reduce usage of operator LPCWSTR from CFX_WideString().

core/src/fxcrt/fx_basic_wstring.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/fxcrt/fx_basic.h"
 #include "../../../third_party/base/numerics/safe_math.h"
 
 static CFX_StringDataW* FX_AllocStringW(int nLen)
@@ skipping 1044 matching lines @@
 {
     if (m_pData == NULL) {
         return 0.0;
     }
     return FX_wtof(m_pData->m_String, m_pData->m_nDataLength);
 }
 static CFX_ByteString _DefMap_GetByteString(CFX_CharMap* pCharMap, const CFX_WideString& widestr)
 {
     int src_len = widestr.GetLength();
     int codepage = pCharMap->m_GetCodePage ? pCharMap->m_GetCodePage() : 0;
-    int dest_len = FXSYS_WideCharToMultiByte(codepage, 0, widestr, src_len, NULL, 0, NULL, NULL);
+    int dest_len = FXSYS_WideCharToMultiByte(codepage, 0, widestr.c_str(), src_len, NULL, 0, NULL, NULL);
     if (dest_len == 0) {
         return CFX_ByteString();
     }
     CFX_ByteString bytestr;
     FX_LPSTR dest_buf = bytestr.GetBuffer(dest_len);
-    FXSYS_WideCharToMultiByte(codepage, 0, widestr, src_len, dest_buf, dest_len, NULL, NULL);
+    FXSYS_WideCharToMultiByte(codepage, 0, widestr.c_str(), src_len, dest_buf, dest_len, NULL, NULL);
     bytestr.ReleaseBuffer(dest_len);
     return bytestr;
 }
 static CFX_WideString _DefMap_GetWideString(CFX_CharMap* pCharMap, const CFX_ByteString& bytestr)
 {
     int src_len = bytestr.GetLength();
     int codepage = pCharMap->m_GetCodePage ? pCharMap->m_GetCodePage() : 0;
     int dest_len = FXSYS_MultiByteToWideChar(codepage, 0, bytestr, src_len, NULL, 0);
     if (dest_len == 0) {
         return CFX_WideString();
@@ skipping 34 matching lines @@
             return (CFX_CharMap*)&g_DefaultJISMapper;
         case 936:
             return (CFX_CharMap*)&g_DefaultGBKMapper;
         case 949:
             return (CFX_CharMap*)&g_DefaultUHCMapper;
         case 950:
             return (CFX_CharMap*)&g_DefaultBig5Mapper;
     }
     return NULL;
 }