include RefCounted.h where needed, only.

third_party/WebKit/Source/core/animation/Interpolation.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 Interpolation_h
 #define Interpolation_h
 
 #include "core/CoreExport.h"
 #include "core/animation/InterpolableValue.h"
-#include "platform/heap/Handle.h"
+#include "wtf/Forward.h"
+#include "wtf/RefCounted.h"
 
 namespace blink {
 
 class PropertyHandle;
 
 // Represents an animation's effect between an adjacent pair of PropertySpecificKeyframes.
 class CORE_EXPORT Interpolation : public RefCounted<Interpolation> {
     WTF_MAKE_NONCOPYABLE(Interpolation);
 public:
     virtual ~Interpolation();
@@ skipping 24 matching lines @@
     friend class AnimationInterpolationEffectTest;
     friend class AnimationDoubleStyleInterpolationTest;
     friend class AnimationVisibilityStyleInterpolationTest;
 };
 
 using ActiveInterpolations = Vector<RefPtr<Interpolation>, 1>;
 
 } // namespace blink
 
 #endif // Interpolation_h