Eliminate HAVE(ERRNO_H) guard.

Source/wtf/ThreadingWin.cpp

 /*
  * Copyright (C) 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile, 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
@@ skipping 89 matching lines @@
 #include "wtf/MathExtras.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/RandomNumberSeed.h"
 #include "wtf/WTFThreadData.h"
 
 #if !USE(PTHREADS) && OS(WINDOWS)
 #include "ThreadSpecific.h"
 #endif
 
+#include <errno.h>
 #include <process.h>
 
-#if HAVE(ERRNO_H)
-#include <errno.h>
-#endif
-
 namespace WTF {
 
 // MS_VC_EXCEPTION, THREADNAME_INFO, and setThreadNameInternal all come from <http://msdn.microsoft.com/en-us/library/xcb2z8hs.aspx>.
 static const DWORD MS_VC_EXCEPTION = 0x406D1388;
 
 #pragma pack(push, 8)
 typedef struct tagTHREADNAME_INFO {
     DWORD dwType; // must be 0x1000
     LPCSTR szName; // pointer to name (in user addr space)
     DWORD dwThreadID; // thread ID (-1=caller thread)
@@ skipping 90 matching lines @@
     return 0;
 }
 
 ThreadIdentifier createThreadInternal(ThreadFunction entryPoint, void* data, const char* threadName)
 {
     unsigned threadIdentifier = 0;
     ThreadIdentifier threadID = 0;
     OwnPtr<ThreadFunctionInvocation> invocation = adoptPtr(new ThreadFunctionInvocation(entryPoint, data));
     HANDLE threadHandle = reinterpret_cast<HANDLE>(_beginthreadex(0, 0, wtfThreadEntryPoint, invocation.get(), 0, &threadIdentifier));
     if (!threadHandle) {
-#if !HAVE(ERRNO_H)
-        LOG_ERROR("Failed to create thread at entry point %p with data %p.", entryPoint, data);
-#else
         LOG_ERROR("Failed to create thread at entry point %p with data %p: %ld", entryPoint, data, errno);
-#endif
         return 0;
     }
 
     // The thread will take ownership of invocation.
     ThreadFunctionInvocation* leakedInvocation = invocation.leakPtr();
     UNUSED_PARAM(leakedInvocation);
 
     threadID = static_cast<ThreadIdentifier>(threadIdentifier);
     storeThreadHandleByIdentifier(threadIdentifier, threadHandle);
 
@@ skipping 257 matching lines @@
     // Time is too far in the future (and would overflow unsigned long) - wait forever.
     if (absoluteTime - currentTime > static_cast<double>(INT_MAX) / 1000.0)
         return INFINITE;
 
     return static_cast<DWORD>((absoluteTime - currentTime) * 1000.0);
 }
 
 } // namespace WTF
 
 #endif // OS(WINDOWS)