Remove RuntimeEnabledFeatures.h includes from a few headers

Source/platform/animation/TimingFunction.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 
 #ifndef TimingFunction_h
 #define TimingFunction_h
 
-#include "RuntimeEnabledFeatures.h"
 #include "platform/animation/AnimationUtilities.h" // For blend()
 #include "platform/animation/UnitBezier.h"
 #include "wtf/OwnPtr.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/PassRefPtr.h"
 #include "wtf/RefCounted.h"
 #include "wtf/StdLibExtras.h"
 #include "wtf/Vector.h"
 #include "wtf/text/StringBuilder.h"
 #include "wtf/text/WTFString.h"
@@ skipping 208 matching lines @@
         value->type() == TimingFunction::typeName##Function, \
         value.type() == TimingFunction::typeName##Function)
 
 DEFINE_TIMING_FUNCTION_TYPE_CASTS(Linear);
 DEFINE_TIMING_FUNCTION_TYPE_CASTS(CubicBezier);
 DEFINE_TIMING_FUNCTION_TYPE_CASTS(Steps);
 
 } // namespace WebCore
 
 #endif // TimingFunction_h