Revert "Remove support for MSVC"

sky/engine/wtf/text/WTFString.cpp

 /*
  * (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2007-2009 Torch Mobile, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 451 matching lines @@
 }
 
 String String::format(const char *format, ...)
 {
     va_list args;
     va_start(args, format);
 
     Vector<char, 256> buffer;
 
     // Do the format once to get the length.
+#if COMPILER(MSVC)
+    int result = _vscprintf(format, args);
+#else
     char ch;
     int result = vsnprintf(&ch, 1, format, args);
     // We need to call va_end() and then va_start() again here, as the
     // contents of args is undefined after the call to vsnprintf
     // according to http://man.cx/snprintf(3)
     //
     // Not calling va_end/va_start here happens to work on lots of
     // systems, but fails e.g. on 64bit Linux.
     va_end(args);
     va_start(args, format);
+#endif
 
     if (result == 0)
         return String("");
     if (result < 0)
         return String();
     unsigned len = result;
     buffer.grow(len + 1);
 
     // Now do the formatting again, guaranteed to fit.
     vsnprintf(buffer.data(), buffer.size(), format, args);
@@ skipping 512 matching lines @@
         else
             digitValue = c - 'A' + 10;
 
         if (value > maxMultiplier || (value == maxMultiplier && digitValue > (integralMax % base) + isNegative))
             goto bye;
 
         value = base * value + digitValue;
         ++data;
     }
 
+#if COMPILER(MSVC)
+#pragma warning(push, 0)
+#pragma warning(disable:4146)
+#endif
+
     if (isNegative)
         value = -value;
 
+#if COMPILER(MSVC)
+#pragma warning(pop)
+#endif
+
     // skip trailing space
     while (length && isSpaceOrNewline(*data)) {
         --length;
         ++data;
     }
 
     if (!length)
         isOk = true;
 bye:
     if (ok)
@@ skipping 231 matching lines @@
     buffer.append('\0');
     return buffer;
 }
 
 Vector<char> asciiDebug(String& string)
 {
     return asciiDebug(string.impl());
 }
 
 #endif