Implemented additive animations for length

Source/core/animation/css/CSSAnimations.h

 /*
  * 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 15 matching lines @@
  * 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.
  */
 
 #ifndef CSSAnimations_h
 #define CSSAnimations_h
 
 #include "core/animation/InertAnimation.h"
 #include "core/animation/Interpolation.h"
+#include "core/animation/InterpolationPipeline.h"
 #include "core/animation/css/CSSAnimationData.h"
 #include "core/animation/css/CSSAnimationUpdate.h"
 #include "core/css/CSSKeyframesRule.h"
 #include "core/css/StylePropertySet.h"
 #include "core/dom/Document.h"
 #include "core/dom/Element.h"
 #include "wtf/HashMap.h"
 #include "wtf/text/AtomicString.h"
 
 namespace blink {
@@ skipping 69 matching lines @@
     };
 
     using AnimationMap = WillBeHeapHashMap<AtomicString, RefPtrWillBeMember<RunningAnimation>>;
     AnimationMap m_animations;
 
     using TransitionMap = WillBeHeapHashMap<CSSPropertyID, RunningTransition>;
     TransitionMap m_transitions;
 
     OwnPtrWillBeMember<CSSAnimationUpdate> m_pendingUpdate;
 
-    WillBeHeapHashMap<CSSPropertyID, RefPtrWillBeMember<Interpolation>> m_previousActiveInterpolationsForAnimations;
+    InterpolationPipelineMap m_previousActiveInterpolationsForAnimations;
 
     static void calculateAnimationUpdate(CSSAnimationUpdate*, const Element* animatingElement, Element&, const LayoutStyle&, LayoutStyle* parentStyle, StyleResolver*);
     static void calculateTransitionUpdate(CSSAnimationUpdate*, const Element* animatingElement, const LayoutStyle&);
     static void calculateTransitionUpdateForProperty(CSSPropertyID, CSSPropertyID eventId, const CSSTransitionData&, size_t transitionIndex, const LayoutStyle& oldStyle, const LayoutStyle&, const TransitionMap* activeTransitions, CSSAnimationUpdate*, const Element*);
 
     static void calculateAnimationActiveInterpolations(CSSAnimationUpdate*, const Element* animatingElement, double timelineCurrentTime);
     static void calculateTransitionActiveInterpolations(CSSAnimationUpdate*, const Element* animatingElement, double timelineCurrentTime);
 
     class AnimationEventDelegate final : public AnimationNode::EventDelegate {
     public:
@@ skipping 40 matching lines @@
 
         RawPtrWillBeMember<Element> m_transitionTarget;
         const CSSPropertyID m_property;
         AnimationNode::Phase m_previousPhase;
     };
 };
 
 } // namespace blink
 
 #endif