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

third_party/WebKit/Source/core/animation/KeyframeInterpolation.h

Index: third_party/WebKit/Source/core/animation/KeyframeInterpolation.h
diff --git a/third_party/WebKit/Source/core/animation/InvalidatableInterpolation.h b/third_party/WebKit/Source/core/animation/KeyframeInterpolation.h
similarity index 67%
rename from third_party/WebKit/Source/core/animation/InvalidatableInterpolation.h
rename to third_party/WebKit/Source/core/animation/KeyframeInterpolation.h
index 88430934824ade771888b7cd7c378f66db01ec6d..dccdc081a98fc68bb13d6819dcc38fd543566500 100644
--- a/third_party/WebKit/Source/core/animation/InvalidatableInterpolation.h
+++ b/third_party/WebKit/Source/core/animation/KeyframeInterpolation.h
@@ -2,80 +2,79 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef InvalidatableInterpolation_h
-#define InvalidatableInterpolation_h
+#ifndef KeyframeInterpolation_h
+#define KeyframeInterpolation_h
 
 #include "core/animation/InterpolationType.h"
+#include "core/animation/Keyframe.h"
 #include "core/animation/PrimitiveInterpolation.h"
 #include "core/animation/PropertyInterpolationTypesMapping.h"
-#include "core/animation/StyleInterpolation.h"
-#include "core/animation/TypedInterpolationValue.h"
+#include "core/animation/StackableInterpolation.h"
 #include <memory>
 
 namespace blink {
 
 // TODO(alancutter): This class will replace *StyleInterpolation and Interpolation.
 // For now it needs to distinguish itself during the refactor and temporarily has an ugly name.
-class CORE_EXPORT InvalidatableInterpolation : public Interpolation {
+class KeyframeInterpolation : public StackableInterpolation {
 public:
-    static PassRefPtr<InvalidatableInterpolation> create(
+    static PassRefPtr<KeyframeInterpolation> create(
         PropertyHandle property,
         const InterpolationTypes& interpolationTypes,
         PassRefPtr<PropertySpecificKeyframe> startKeyframe,
         PassRefPtr<PropertySpecificKeyframe> endKeyframe)
     {
-        return adoptRef(new InvalidatableInterpolation(property, interpolationTypes, startKeyframe, endKeyframe));
+        return adoptRef(new KeyframeInterpolation(property, interpolationTypes, startKeyframe, endKeyframe));
     }
 
     PropertyHandle getProperty() const final { return m_property; }
-    virtual void interpolate(int iteration, double fraction);
     bool dependsOnUnderlyingValue() const final;
-    virtual void apply(InterpolationEnvironment&) const { NOTREACHED(); }
     static void applyStack(const ActiveInterpolations&, InterpolationEnvironment&);
 
-    virtual bool isInvalidatableInterpolation() const { return true; }
+    virtual bool isKeyframeInterpolation() const { return true; }
 
 private:
-    InvalidatableInterpolation(
+    KeyframeInterpolation(
         PropertyHandle property,
         const InterpolationTypes& interpolationTypes,
         PassRefPtr<PropertySpecificKeyframe> startKeyframe,
         PassRefPtr<PropertySpecificKeyframe> endKeyframe)
-        : Interpolation(nullptr, nullptr)
-        , m_property(property)
+        : m_property(property)
         , m_interpolationTypes(interpolationTypes)
         , m_startKeyframe(startKeyframe)
         , m_endKeyframe(endKeyframe)
-        , m_currentFraction(std::numeric_limits<double>::quiet_NaN())
+        , m_previousFraction(std::numeric_limits<double>::quiet_NaN())
         , m_isCached(false)
     { }
 
     using ConversionCheckers = InterpolationType::ConversionCheckers;
 
-    std::unique_ptr<TypedInterpolationValue> maybeConvertUnderlyingValue(const InterpolationEnvironment&) const;
-    const TypedInterpolationValue* ensureValidInterpolation(const InterpolationEnvironment&, const UnderlyingValueOwner&) const;
+    void interpolateImpl() final;
+    std::unique_ptr<TypedInterpolationValue> maybeConvertUnderlyingValue(const InterpolationEnvironment&) const final;
+    const TypedInterpolationValue* ensureValidInterpolation(const InterpolationEnvironment&, const UnderlyingValueOwner&) const final;
+    void setFlagIfInheritUsed(InterpolationEnvironment&) const final;
+    double underlyingFraction() const final;
+
     void clearCache() const;
     bool isCacheValid(const InterpolationEnvironment&, const UnderlyingValueOwner&) const;
     bool isNeutralKeyframeActive() const;
     std::unique_ptr<PairwisePrimitiveInterpolation> maybeConvertPairwise(const InterpolationEnvironment&, const UnderlyingValueOwner&) const;
     std::unique_ptr<TypedInterpolationValue> convertSingleKeyframe(const PropertySpecificKeyframe&, const InterpolationEnvironment&, const UnderlyingValueOwner&) const;
     void addConversionCheckers(const InterpolationType&, ConversionCheckers&) const;
-    void setFlagIfInheritUsed(InterpolationEnvironment&) const;
-    double underlyingFraction() const;
 
     const PropertyHandle m_property;
     const InterpolationTypes& m_interpolationTypes;
     RefPtr<PropertySpecificKeyframe> m_startKeyframe;
     RefPtr<PropertySpecificKeyframe> m_endKeyframe;
-    double m_currentFraction;
+    double m_previousFraction;
     mutable bool m_isCached;
     mutable std::unique_ptr<PrimitiveInterpolation> m_cachedPairConversion;
     mutable ConversionCheckers m_conversionCheckers;
     mutable std::unique_ptr<TypedInterpolationValue> m_cachedValue;
 };
 
-DEFINE_TYPE_CASTS(InvalidatableInterpolation, Interpolation, value, value->isInvalidatableInterpolation(), value.isInvalidatableInterpolation());
+DEFINE_TYPE_CASTS(KeyframeInterpolation, Interpolation, value, value->isKeyframeInterpolation(), value.isKeyframeInterpolation());
 
 } // namespace blink
 
-#endif // InvalidatableInterpolation_h
+#endif // KeyframeInterpolation_h