Move Animatable* hierarchy into new folder.

Source/core/animation/animatable/AnimatableLengthBox.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 11 matching lines @@
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * 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 "config.h"
-#include "core/animation/AnimatableLengthBox.h"
+#include "core/animation/animatable/AnimatableLengthBox.h"
 
 namespace WebCore {
 
 PassRefPtrWillBeRawPtr<AnimatableValue> AnimatableLengthBox::interpolateTo(const AnimatableValue* value, double fraction) const
 {
     const AnimatableLengthBox* lengthBox = toAnimatableLengthBox(value);
     return AnimatableLengthBox::create(
         AnimatableValue::interpolate(this->left(), lengthBox->left(), fraction),
         AnimatableValue::interpolate(this->right(), lengthBox->right(), fraction),
         AnimatableValue::interpolate(this->top(), lengthBox->top(), fraction),
@@ skipping 12 matching lines @@
 void AnimatableLengthBox::trace(Visitor* visitor)
 {
     visitor->trace(m_left);
     visitor->trace(m_right);
     visitor->trace(m_top);
     visitor->trace(m_bottom);
     AnimatableValue::trace(visitor);
 }
 
 }