Delete unused AnimatableValue code

third_party/WebKit/Source/core/animation/animatable/AnimatableVisibility.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 14 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "core/animation/animatable/AnimatableVisibility.h"
 
 namespace blink {
 
-bool AnimatableVisibility::usesDefaultInterpolationWith(
-    const AnimatableValue* value) const {
-  EVisibility from = m_visibility;
-  EVisibility to = toAnimatableVisibility(value)->m_visibility;
-  return from != EVisibility::kVisible && to != EVisibility::kVisible;
-}
-
-PassRefPtr<AnimatableValue> AnimatableVisibility::interpolateTo(
-    const AnimatableValue* value,
-    double fraction) const {
-  EVisibility from = m_visibility;
-  EVisibility to = toAnimatableVisibility(value)->m_visibility;
-  if (from != EVisibility::kVisible && to != EVisibility::kVisible)
-    return defaultInterpolateTo(this, value, fraction);
-  if (fraction <= 0)
-    return takeConstRef(this);
-  if (fraction >= 1)
-    return takeConstRef(value);
-  return takeConstRef(from == EVisibility::kVisible ? this : value);
-}
-
 bool AnimatableVisibility::equalTo(const AnimatableValue* value) const {
   return m_visibility == toAnimatableVisibility(value)->m_visibility;
 }
 
 }  // namespace blink