Avoid useless initialization in ScrollAnimatorNone::PerAxisData::animateScroll()

Source/platform/scroll/ScrollAnimatorNone.h

 /*
  * Copyright (c) 2011, 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 93 matching lines @@
 
         static double curveAt(Curve, double t);
         static double attackCurve(Curve, double deltaT, double curveT, double startPos, double attackPos);
         static double releaseCurve(Curve, double deltaT, double curveT, double releasePos, double desiredPos);
         static double coastCurve(Curve, double factor);
 
         static double curveIntegralAt(Curve, double t);
         static double attackArea(Curve, double startT, double endT);
         static double releaseArea(Curve, double startT, double endT);
 
+        double newScrollAnimationPosition(double deltaTime);
+
         float* m_currentPosition;
         double m_currentVelocity;
 
         double m_desiredPosition;
         double m_desiredVelocity;
 
         double m_startPosition;
         double m_startTime;
         double m_startVelocity;
 
@@ skipping 21 matching lines @@
     PerAxisData m_horizontalData;
     PerAxisData m_verticalData;
 
     double m_startTime;
     bool m_animationActive;
 };
 
 } // namespace WebCore
 
 #endif // ScrollAnimatorNone_h