Remove some unused functions in core

Source/core/animation/animatable/AnimatableValue.h

Index: Source/core/animation/animatable/AnimatableValue.h
diff --git a/Source/core/animation/animatable/AnimatableValue.h b/Source/core/animation/animatable/AnimatableValue.h
index 9aef5917e102bbf5375bea90e4ccae2425856b15..0790dc6b9f466036c0cc110d8a4f74538f9cf3c0 100644
--- a/Source/core/animation/animatable/AnimatableValue.h
+++ b/Source/core/animation/animatable/AnimatableValue.h
@@ -44,7 +44,6 @@ public:
     static const AnimatableValue* neutralValue();
 
     static PassRefPtrWillBeRawPtr<AnimatableValue> interpolate(const AnimatableValue*, const AnimatableValue*, double fraction);
-    static double distance(const AnimatableValue* from, const AnimatableValue* to);
     static bool usesDefaultInterpolation(const AnimatableValue* from, const AnimatableValue* to)
     {
         return !from->isSameType(to) || from->usesDefaultInterpolationWith(to);
@@ -128,8 +127,6 @@ private:
     // Implementations can assume that the object being compared has the same type as the object this is called on
     virtual bool equalTo(const AnimatableValue*) const = 0;
 
-    virtual double distanceTo(const AnimatableValue*) const;
-
     template <class Keyframe> friend class KeyframeEffectModel;
 };