Move Animatable* hierarchy into new folder.

Source/core/animation/animatable/AnimatableLengthTest.cpp

 // 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.
 
 #include "config.h"
 
-#include "core/animation/AnimatableLength.h"
+#include "core/animation/animatable/AnimatableLength.h"
+
 #include "platform/CalculationValue.h"
 
 #include <gtest/gtest.h>
 
 namespace WebCore {
 
 namespace {
 
     PassRefPtrWillBeRawPtr<AnimatableLength> create(const Length& length, double zoom = 1)
     {
@@ skipping 46 matching lines @@
 
 TEST(AnimationAnimatableLengthTest, Interpolate)
 {
     EXPECT_TRUE(AnimatableValue::interpolate(create(Length(10, Fixed)).get(), create(Length(0, Fixed)).get(), 0.2)->equals(create(Length(8, Fixed)).get()));
     EXPECT_TRUE(AnimatableValue::interpolate(create(Length(4, Percent)).get(), create(Length(12, Percent)).get(), 0.25)->equals(create(Length(6, Percent)).get()));
     Length calc = Length(CalculationValue::create(PixelsAndPercent(12, 4), ValueRangeAll));
     EXPECT_TRUE(AnimatableValue::interpolate(create(Length(20, Fixed)).get(), create(Length(10, Percent)).get(), 0.4)->equals(create(calc).get()));
 }
 
 } // namespace WebCore