WIP: Implement CSS transitions on top of InterpolationTypes instead of AnimatableValues

third_party/WebKit/Source/core/animation/StyleInterpolation.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 StyleInterpolation_h
 #define StyleInterpolation_h
 
 #include "core/CSSPropertyNames.h"
 #include "core/CoreExport.h"
 #include "core/animation/Interpolation.h"
 #include "core/animation/PropertyHandle.h"
 #include <memory>
 
 namespace blink {
 
 class StyleResolverState;
 
-enum InterpolationRange {
-    RangeAll,
-    RangeFloor,
-    RangeGreaterThanOrEqualToOne,
-    RangeNonNegative,
-    RangeRound,
-    RangeRoundGreaterThanOrEqualToOne,
-    RangeOpacityFIXME,
-    RangeZeroToOne
-};
-
 class CORE_EXPORT StyleInterpolation : public Interpolation {
 public:
     // 1) convert m_cachedValue into an X
     // 2) shove X into StyleResolverState
     // X can be:
     // (1) a CSSValue (and applied via StyleBuilder::applyProperty)
     // (2) an AnimatableValue (and applied via // AnimatedStyleBuilder::applyProperty)
     // (3) a custom value that is inserted directly into the StyleResolverState.
     virtual void apply(StyleResolverState&) const = 0;
 
     bool isStyleInterpolation() const final { return true; }
 
     CSSPropertyID id() const { return m_id; }
 
     PropertyHandle getProperty() const final
     {
         return PropertyHandle(id());
     }
 
 protected:
-    CSSPropertyID m_id;
+    StyleInterpolation(std::unique_ptr<InterpolableValue> start, std::unique_ptr<InterpolableValue> end, CSSPropertyID);
 
-    StyleInterpolation(std::unique_ptr<InterpolableValue> start, std::unique_ptr<InterpolableValue> end, CSSPropertyID id)
-        : Interpolation(std::move(start), std::move(end))
-        , m_id(id)
-    {
-    }
+    void interpolateImpl() final;
+
+    const std::unique_ptr<InterpolableValue> m_start;
+    const std::unique_ptr<InterpolableValue> m_end;
+    const CSSPropertyID m_id;
+
+    mutable std::unique_ptr<InterpolableValue> m_cachedValue;
+
+private:
+    InterpolableValue* getCachedValueForTesting() const { return m_cachedValue.get(); }
+
+    friend class AnimationInterpolableValueTest;
+    friend class AnimationInterpolationEffectTest;
 };
 
 DEFINE_TYPE_CASTS(StyleInterpolation, Interpolation, value, value->isStyleInterpolation(), value.isStyleInterpolation());
 
 } // namespace blink
 
 #endif