Rename OS(WINDOWS) to OS(WIN)

Source/wtf/Assertions.h

 /*
  * Copyright (C) 2003, 2006, 2007 Apple Inc.  All rights reserved.
  * 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 162 matching lines @@
     WTFReportBacktrace(); \
 } while(false)
 
 #endif
 
 /* ASSERT, ASSERT_NOT_REACHED, ASSERT_UNUSED
 
   These macros are compiled out of release builds.
   Expressions inside them are evaluated in debug builds only.
 */
-#if OS(WINDOWS)
+#if OS(WIN)
 /* FIXME: Change to use something other than ASSERT to avoid this conflict with the underlying platform */
 #undef ASSERT
 #endif
 
 #if ASSERT_DISABLED
 
 #define ASSERT(assertion) ((void)0)
 #define ASSERT_AT(assertion, file, line, function) ((void)0)
 #define ASSERT_NOT_REACHED() ((void)0)
 #define NO_RETURN_DUE_TO_ASSERT
@@ skipping 170 matching lines @@
 #define RELEASE_ASSERT(assertion) (UNLIKELY(!(assertion)) ? (IMMEDIATE_CRASH()) : (void)0)
 #define RELEASE_ASSERT_WITH_MESSAGE(assertion, ...) RELEASE_ASSERT(assertion)
 #define RELEASE_ASSERT_NOT_REACHED() IMMEDIATE_CRASH()
 #else
 #define RELEASE_ASSERT(assertion) ASSERT(assertion)
 #define RELEASE_ASSERT_WITH_MESSAGE(assertion, ...) ASSERT_WITH_MESSAGE(assertion, __VA_ARGS__)
 #define RELEASE_ASSERT_NOT_REACHED() ASSERT_NOT_REACHED()
 #endif
 
 #endif /* WTF_Assertions_h */