Added errno (or GetLastError code) to crash dump when systemAllocPages fails.

third_party/WebKit/Source/wtf/PageAllocator.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 118 matching lines @@
 WTF_EXPORT ALWAYS_INLINE uintptr_t roundUpToSystemPage(uintptr_t address)
 {
     return (address + kSystemPageOffsetMask) & kSystemPageBaseMask;
 }
 
 WTF_EXPORT ALWAYS_INLINE uintptr_t roundDownToSystemPage(uintptr_t address)
 {
     return address & kSystemPageBaseMask;
 }
 
+// Only allowed inside WTF for investigating WTF::initializeWithoutV8 crashes.
+// Guess, the function fails because of mmap (or VirtualAlloc) failure.
+// The following function returns errno (or GetLastError code) when mmap
+// (or VirtualAlloc) fails.
+uint32_t getAllocPageErrorCode();
+
 } // namespace WTF
 
 #endif // WTF_PageAllocator_h