Oilpan build fix for r174893 and r174900.

Source/core/animation/interpolation/DeferredLegacyStyleInterpolation.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/DeferredLegacyStyleInterpolation.h"
 
 #include "core/animation/interpolation/LegacyStyleInterpolation.h"
 #include "core/css/CSSImageValue.h"
 #include "core/css/CSSPrimitiveValue.h"
@@ skipping 126 matching lines @@
 }
 
 bool DeferredLegacyStyleInterpolation::interpolationRequiresStyleResolve(const CSSBasicShape& shape)
 {
     // FIXME: Should determine the specific shape, and inspect the members.
     return false;
 }
 
 void DeferredLegacyStyleInterpolation::trace(Visitor* visitor)
 {
-    StyleInterpolation::trace(visitor);
     visitor->trace(m_startCSSValue);
     visitor->trace(m_endCSSValue);
+    StyleInterpolation::trace(visitor);
 }
 
 }