Remove unused code in InvalidatableInterpolation

third_party/WebKit/Source/core/animation/LegacyStyleInterpolation.h

Index: third_party/WebKit/Source/core/animation/LegacyStyleInterpolation.h
diff --git a/third_party/WebKit/Source/core/animation/LegacyStyleInterpolation.h b/third_party/WebKit/Source/core/animation/LegacyStyleInterpolation.h
index 0947a3c1b327267e14daea6ee1aa61c23e4441f3..44efdf39a6d389c22d549a1f8672d3593b4f023d 100644
--- a/third_party/WebKit/Source/core/animation/LegacyStyleInterpolation.h
+++ b/third_party/WebKit/Source/core/animation/LegacyStyleInterpolation.h
@@ -64,9 +64,12 @@ class CORE_EXPORT LegacyStyleInterpolation : public Interpolation {
   mutable int m_cachedIteration;
   mutable std::unique_ptr<InterpolableValue> m_cachedValue;
 
-  InterpolableValue* getCachedValueForTesting() const final {
+  InterpolableValue* getCachedValueForTesting() const {
     return m_cachedValue.get();
   }
+
+  friend class AnimationInterpolableValueTest;
+  friend class AnimationInterpolationEffectTest;
 };
 
 DEFINE_TYPE_CASTS(LegacyStyleInterpolation,