Add last OS error into heap stats.

src/platform-posix.cc

 // Copyright 2009 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 90 matching lines @@
 
 double OS::DaylightSavingsOffset(double time) {
   if (isnan(time)) return nan_value();
   time_t tv = static_cast<time_t>(floor(time/msPerSecond));
   struct tm* t = localtime(&tv);
   if (NULL == t) return nan_value();
   return t->tm_isdst > 0 ? 3600 * msPerSecond : 0;
 }
 
 
+int OS::GetLastError() {
+  return errno;
+}
+
+
 // ----------------------------------------------------------------------------
 // POSIX stdio support.
 //
 
 FILE* OS::FOpen(const char* path, const char* mode) {
   return fopen(path, mode);
 }
 
 
 const char* OS::LogFileOpenMode = "w";
@@ skipping 232 matching lines @@
   return ntohl(value);
 }
 
 
 Socket* OS::CreateSocket() {
   return new POSIXSocket();
 }
 
 
 } }  // namespace v8::internal