InlinedVisitor: Migrate animation to use inlined tracing

Source/core/animation/Interpolation.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/animation/Interpolation.h"
 
 namespace blink {
 
 namespace {
@@ skipping 37 matching lines @@
 
 void Interpolation::interpolate(int iteration, double fraction) const
 {
     if (m_cachedFraction != fraction || m_cachedIteration != iteration) {
         m_start->interpolate(*m_end, fraction, *m_cachedValue);
         m_cachedIteration = iteration;
         m_cachedFraction = fraction;
     }
 }
 
-void Interpolation::trace(Visitor* visitor)
+DEFINE_TRACE(Interpolation)
 {
     visitor->trace(m_start);
     visitor->trace(m_end);
     visitor->trace(m_cachedValue);
 }
 
 }