Make CFX_WideString(const CFX_WideString&) explicit.

core/fxcrt/fx_basic_buffer.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 <algorithm>
 #include <limits>
 
 #include "core/fxcrt/include/fx_basic.h"
@@ skipping 168 matching lines @@
 CFX_WideTextBuf& CFX_WideTextBuf::operator<<(const FX_WCHAR* lpsz) {
   AppendBlock(lpsz, FXSYS_wcslen(lpsz) * sizeof(FX_WCHAR));
   return *this;
 }
 
 CFX_WideTextBuf& CFX_WideTextBuf::operator<<(const CFX_WideTextBuf& buf) {
   AppendBlock(buf.m_pBuffer.get(), buf.m_DataSize);
   return *this;
 }
 
-CFX_WideStringC CFX_WideTextBuf::AsStringC() const {
-  return CFX_WideStringC(reinterpret_cast<const FX_WCHAR*>(m_pBuffer.get()),
-                         m_DataSize / sizeof(FX_WCHAR));
-}
-
 #ifdef PDF_ENABLE_XFA
 CFX_ArchiveSaver& CFX_ArchiveSaver::operator<<(uint8_t i) {
   if (m_pStream) {
     m_pStream->WriteBlock(&i, 1);
   } else {
     m_SavingBuf.AppendByte(i);
   }
   return *this;
 }
 CFX_ArchiveSaver& CFX_ArchiveSaver::operator<<(int i) {
@@ skipping 215 matching lines @@
 }
 
 int32_t CFX_FileBufferArchive::AppendString(const CFX_ByteStringC& lpsz) {
   return AppendBlock(lpsz.raw_str(), lpsz.GetLength());
 }
 
 void CFX_FileBufferArchive::AttachFile(IFX_StreamWrite* pFile) {
   ASSERT(pFile);
   m_pFile = pFile;
 }