Explicity use CFX_ByteStrings in a couple of places

core/fpdfapi/fpdf_font/fpdf_font.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 "core/fpdfapi/fpdf_font/font_int.h"
 
 #include "core/fpdfapi/fpdf_page/include/cpdf_form.h"
 #include "core/fpdfapi/fpdf_page/pageint.h"
@@ skipping 221 matching lines @@
         if (low.IsEmpty() || low == "endbfrange") {
           break;
         }
         high = parser.GetWord();
         uint32_t lowcode = StringToCode(low.AsStringC());
         uint32_t highcode =
             (lowcode & 0xffffff00) | (StringToCode(high.AsStringC()) & 0xff);
         if (highcode == (uint32_t)-1) {
           break;
         }
-        CFX_ByteString start = parser.GetWord();
+        CFX_ByteString start(parser.GetWord());
         if (start == "[") {
           for (uint32_t code = lowcode; code <= highcode; code++) {
-            CFX_ByteString dest = parser.GetWord();
+            CFX_ByteString dest(parser.GetWord());
             CFX_WideString destcode = StringToWideString(dest.AsStringC());
             int len = destcode.GetLength();
             if (len == 0) {
               continue;
             }
             if (len == 1) {
               m_Map[code] = destcode.GetAt(0);
             } else {
               m_Map[code] = m_MultiCharBuf.GetLength() * 0x10000 + 0xffff;
               m_MultiCharBuf.AppendChar(destcode.GetLength());
@@ skipping 38 matching lines @@
   }
   if (cid_set) {
     m_pBaseMap = CPDF_ModuleMgr::Get()
                      ->GetPageModule()
                      ->GetFontGlobals()
                      ->m_CMapManager.GetCID2UnicodeMap(cid_set, FALSE);
   } else {
     m_pBaseMap = NULL;
   }
 }