Make down-conversion explicit from CFX_Widetring to CFX_WideStringC.

xfa/fxfa/parser/xfa_document_serialize.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 "xfa/fxfa/parser/xfa_document_serialize.h"
 
 #include "xfa/fde/xml/fde_xml_imp.h"
 #include "xfa/fgas/crt/fgas_codepage.h"
@@ skipping 279 matching lines @@
         CFX_WideString bodyTagName;
         bodyTagName = pGrandparentNode->GetCData(XFA_ATTRIBUTE_Name);
         if (bodyTagName.IsEmpty()) {
           bodyTagName = FX_WSTRC(L"ListBox1");
         }
         buf << FX_WSTRC(L"<");
         buf << bodyTagName;
         buf << FX_WSTRC(L" xmlns=\"\"\n>");
         for (int32_t i = 0; i < wsSelTextArray.GetSize(); i++) {
           buf << FX_WSTRC(L"<value\n>");
-          buf << XFA_ExportEncodeContent(wsSelTextArray[i]);
+          buf << XFA_ExportEncodeContent(wsSelTextArray[i].AsWideStringC());
           buf << FX_WSTRC(L"</value\n>");
         }
         buf << FX_WSTRC(L"</");
         buf << bodyTagName;
         buf << FX_WSTRC(L"\n>");
         wsChildren += buf.GetWideString();
         buf.Clear();
       } else {
         CFX_WideStringC wsValue = pRawValueNode->GetCData(XFA_ATTRIBUTE_Value);
         wsChildren += XFA_ExportEncodeContent(wsValue);
@@ skipping 266 matching lines @@
         pXMLElement->RemoveAttribute(L"xfa:dataNode");
       }
     } else {
       CFDE_XMLNode* pXMLNode = pDataNode->GetXMLMappingNode();
       FXSYS_assert(pXMLNode->GetType() == FDE_XMLNODE_Element);
       static_cast<CFDE_XMLElement*>(pXMLNode)
           ->SetString(FX_WSTRC(L"xfa:dataNode"), FX_WSTRC(L"dataGroup"));
     }
   }
 }