XFA: merge patch from CL 733693003, getting rid of more casts

core/src/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 "../../include/fxcrt/fx_basic.h"
 FX_STRSIZE FX_ftoa(FX_FLOAT f, FX_LPSTR buf);
 CFX_BinaryBuf::CFX_BinaryBuf()
     : m_AllocStep(0)
@@ skipping 174 matching lines @@
     *(FX_WCHAR*)(m_pBuffer + m_DataSize) = ch;
     m_DataSize += sizeof(FX_WCHAR);
 }
 CFX_WideTextBuf& CFX_WideTextBuf::operator << (FX_WSTR str)
 {
     AppendBlock(str.GetPtr(), str.GetLength() * sizeof(FX_WCHAR));
     return *this;
 }
 CFX_WideTextBuf& CFX_WideTextBuf::operator << (const CFX_WideString &str)
 {
-    AppendBlock((FX_LPCWSTR)str, str.GetLength() * sizeof(FX_WCHAR));
+    AppendBlock(str.c_str(), str.GetLength() * sizeof(FX_WCHAR));
     return *this;
 }
 CFX_WideTextBuf& CFX_WideTextBuf::operator << (int i)
 {
     char buf[32];
     FXSYS_itoa(i, buf, 10);
     FX_STRSIZE len = (FX_STRSIZE)FXSYS_strlen(buf);
     if (m_AllocSize < m_DataSize + (FX_STRSIZE)(len * sizeof(FX_WCHAR))) {
         ExpandBuf(len * sizeof(FX_WCHAR));
     }
@@ skipping 348 matching lines @@
 FX_BOOL CFX_FileBufferArchive::DoWork(const void* pBuf, size_t size)
 {
     if (!m_pFile) {
         return FALSE;
     }
     if (!pBuf || size < 1) {
         return TRUE;
     }
     return m_pFile->WriteBlock(pBuf, size);
 }