Oilpan: remove redundant WILL_BE_EAGERLY_TRACED() declarations.

Source/core/animation/InterpolableValue.h

 // 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.
 
 #ifndef InterpolableValue_h
 #define InterpolableValue_h
 
 #include "core/animation/animatable/AnimatableValue.h"
 #include "platform/heap/Handle.h"
 #include "wtf/OwnPtr.h"
@@ skipping 20 matching lines @@
     friend class Interpolation;
 
     // Keep interpolate private, but allow calls within the hierarchy without
     // knowledge of type.
     friend class DeferredLegacyStyleInterpolation;
     friend class InterpolableNumber;
     friend class InterpolableBool;
     friend class InterpolableList;
 };
 
-WILL_BE_EAGERLY_TRACED(InterpolableValue);
-
 class InterpolableNumber final : public InterpolableValue {
 public:
     static PassOwnPtrWillBeRawPtr<InterpolableNumber> create(double value)
     {
         return adoptPtrWillBeNoop(new InterpolableNumber(value));
     }
 
     virtual bool isNumber() const override final { return true; }
     double value() const { return m_value; }
     virtual PassOwnPtrWillBeRawPtr<InterpolableValue> clone() const override final { return create(m_value); }
@@ skipping 104 matching lines @@
 };
 
 DEFINE_TYPE_CASTS(InterpolableNumber, InterpolableValue, value, value->isNumber(), value.isNumber());
 DEFINE_TYPE_CASTS(InterpolableBool, InterpolableValue, value, value->isBool(), value.isBool());
 DEFINE_TYPE_CASTS(InterpolableList, InterpolableValue, value, value->isList(), value.isList());
 DEFINE_TYPE_CASTS(InterpolableAnimatableValue, InterpolableValue, value, value->isAnimatableValue(), value.isAnimatableValue());
 
 }
 
 #endif