Rename OS(DARWIN) to OS(MACOSX).

Source/core/platform/graphics/FontCache.h

 /*
  * Copyright (C) 2006, 2008 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2007-2008 Torch Mobile, Inc.
  *
  * 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.
@@ skipping 129 matching lines @@
     PassRefPtr<SimpleFontData> getFontResourceData(const FontPlatformData*, ShouldRetain = Retain);
     const FontPlatformData* getFallbackFontData(const FontDescription&);
 
     // Don't purge if this count is > 0;
     int m_purgePreventCount;
 
 #if OS(WINDOWS) && !ENABLE(GDI_FONTS_ON_WINDOWS)
     OwnPtr<SkFontMgr> m_fontManager;
 #endif
 
-#if OS(DARWIN) || OS(ANDROID)
+#if OS(MACOSX) || OS(ANDROID)
     friend class ComplexTextController;
 #endif
     friend class SimpleFontData; // For getFontResourceData(const FontPlatformData*)
     friend class FontFallbackList;
 };
 
 // Get the global fontCache.
 FontCache* fontCache();
 
 class FontCachePurgePreventer {
 public:
     FontCachePurgePreventer() { fontCache()->disablePurging(); }
     ~FontCachePurgePreventer() { fontCache()->enablePurging(); }
 };
 
 }
 
 #endif