Implement left property animation on InvalidatableStyleInterpolation

Source/core/animation/LengthStyleInterpolation.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 LengthStyleInterpolation_h
 #define LengthStyleInterpolation_h
 
 #include "core/CoreExport.h"
 #include "core/animation/StyleInterpolation.h"
 #include "core/css/CSSPrimitiveValue.h"
@@ skipping 14 matching lines @@
     }
 
     static bool canCreateFrom(const CSSValue&, CSSPropertyID = CSSPropertyInvalid);
 
     void apply(StyleResolverState&) const override;
 
     DECLARE_VIRTUAL_TRACE();
 
     static PassOwnPtrWillBeRawPtr<InterpolableValue> toInterpolableValue(const CSSValue&, CSSPropertyID = CSSPropertyInvalid);
     static PassRefPtrWillBeRawPtr<CSSPrimitiveValue> fromInterpolableValue(const InterpolableValue&, InterpolationRange);
+    static void applyInterpolableValue(CSSPropertyID, const InterpolableValue&, InterpolationRange, StyleResolverState&, LengthSetter);
 
 private:
     LengthStyleInterpolation(PassOwnPtrWillBeRawPtr<InterpolableValue> start, PassOwnPtrWillBeRawPtr<InterpolableValue> end, CSSPropertyID id, InterpolationRange range)
         : StyleInterpolation(start, end, id)
         , m_range(range)
         , m_lengthSetter(nullptr)
     {
         if (isPixelsOrPercentOnly(*m_start) && isPixelsOrPercentOnly(*m_end))
             m_lengthSetter = lengthSetterForProperty(id);
     }
 
     static bool isPixelsOrPercentOnly(const InterpolableValue&);
     static LengthSetter lengthSetterForProperty(CSSPropertyID);
 
     InterpolationRange m_range;
     LengthSetter m_lengthSetter;
 };
 
 }
 
 #endif