Clean up forward declarations in Source/platform

Source/platform/text/LocaleMac.h

 /*
  * Copyright (C) 2012 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 25 matching lines @@
 #include "wtf/RetainPtr.h"
 #include "wtf/Vector.h"
 #include "wtf/text/WTFString.h"
 
 OBJC_CLASS NSCalendar;
 OBJC_CLASS NSDateFormatter;
 OBJC_CLASS NSLocale;
 
 namespace blink {
 
-class DateComponents;
-
 class PLATFORM_EXPORT LocaleMac : public Locale {
 public:
     static PassOwnPtr<LocaleMac> create(const String&);
     static PassOwnPtr<LocaleMac> create(NSLocale*);
     ~LocaleMac();
 
     virtual const Vector<String>& weekDayShortLabels() OVERRIDE;
     virtual unsigned firstDayOfWeek() OVERRIDE;
     virtual bool isRTL() OVERRIDE;
 
@@ skipping 33 matching lines @@
     String m_dateTimeFormatWithoutSeconds;
     Vector<String> m_shortMonthLabels;
     Vector<String> m_standAloneMonthLabels;
     Vector<String> m_shortStandAloneMonthLabels;
     Vector<String> m_timeAMPMLabels;
     bool m_didInitializeNumberData;
 };
 
 } // namespace blink
 #endif