Re-enable MSVC warning 4800 for compiling with chromium_code

core/include/fxcrt/fx_string.h

 // 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
 
 #ifndef CORE_INCLUDE_FXCRT_FX_STRING_H_
 #define CORE_INCLUDE_FXCRT_FX_STRING_H_
 
 #include <stdint.h>  // For intptr_t.
@@ skipping 559 matching lines @@
   static FX_STRSIZE WStringLength(const unsigned short* str);
 
   // Explicit conversion to raw string
   const FX_WCHAR* c_str() const { return m_pData ? m_pData->m_String : L""; }
 
   // Implicit conversion to C-style wide string -- deprecated
   operator const FX_WCHAR*() const { return m_pData ? m_pData->m_String : L""; }
 
   void Empty();
 
-  FX_BOOL IsEmpty() const { return !GetLength(); }
+  bool IsEmpty() const { return !GetLength(); }
 
   FX_STRSIZE GetLength() const { return m_pData ? m_pData->m_nDataLength : 0; }
 
   const CFX_WideString& operator=(const FX_WCHAR* str);
 
   const CFX_WideString& operator=(const CFX_WideString& stringSrc);
 
   const CFX_WideString& operator=(const CFX_WideStringC& stringSrc);
 
   const CFX_WideString& operator+=(const FX_WCHAR* str);
@@ skipping 211 matching lines @@
 }
 
 FX_FLOAT FX_atof(const CFX_ByteStringC& str);
 inline FX_FLOAT FX_atof(const CFX_WideStringC& wsStr) {
   return FX_atof(FX_UTF8Encode(wsStr.GetPtr(), wsStr.GetLength()));
 }
 void FX_atonum(const CFX_ByteStringC& str, FX_BOOL& bInteger, void* pData);
 FX_STRSIZE FX_ftoa(FX_FLOAT f, FX_CHAR* buf);
 
 #endif  // CORE_INCLUDE_FXCRT_FX_STRING_H_