Merge to XFA: Fix comparison of CFX_ByteString and CFX_WideString.

core/src/fxcrt/fx_basic_wstring.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 <stddef.h>  // For offsetof().
 
 #include "../../include/fxcrt/fx_basic.h"
 #include "../../../third_party/base/numerics/safe_math.h"
@@ skipping 188 matching lines @@
 {
     if (string.IsEmpty()) {
         return *this;
     }
     ConcatInPlace(string.GetLength(), string.GetPtr());
     return *this;
 }
 bool CFX_WideString::Equal(const wchar_t* ptr) const
 {
     if (!m_pData) {
-        return !ptr;
+        return !ptr || ptr[0] == L'\0';
     }
     if (!ptr) {
-        return false;
+        return m_pData->m_nDataLength == 0;
     }
     return wcslen(ptr) == m_pData->m_nDataLength &&
             wmemcmp(ptr, m_pData->m_String, m_pData->m_nDataLength) == 0;
 }
 bool CFX_WideString::Equal(const CFX_WideStringC& str) const
 {
     if (m_pData == NULL) {
         return str.IsEmpty();
     }
     return str.GetLength() == m_pData->m_nDataLength &&
         wmemcmp(str.GetPtr(), m_pData->m_String, m_pData->m_nDataLength) == 0;
 }
 bool CFX_WideString::Equal(const CFX_WideString& other) const
 {
-    if (!m_pData) {
+    if (IsEmpty()) {
         return other.IsEmpty();
     }
-    if (!other.m_pData) {
+    if (other.IsEmpty()) {
         return false;
     }
     return other.m_pData->m_nDataLength == m_pData->m_nDataLength &&
         wmemcmp(other.m_pData->m_String,
                 m_pData->m_String,
                 m_pData->m_nDataLength) == 0;
 }
 void CFX_WideString::Empty()
 {
     if (m_pData == NULL) {
@@ skipping 864 matching lines @@
             return (CFX_CharMap*)&g_DefaultJISMapper;
         case 936:
             return (CFX_CharMap*)&g_DefaultGBKMapper;
         case 949:
             return (CFX_CharMap*)&g_DefaultUHCMapper;
         case 950:
             return (CFX_CharMap*)&g_DefaultBig5Mapper;
     }
     return NULL;
 }