Preserve running CSS Animations across changes to animation styles according to same name index

third_party/WebKit/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 55 matching lines @@
     void setPendingUpdate(const CSSAnimationUpdate& update)
     {
         clearPendingUpdate();
         m_pendingUpdate.copy(update);
     }
     void clearPendingUpdate()
     {
         m_pendingUpdate.clear();
     }
     void maybeApplyPendingUpdate(Element*);
-    bool isEmpty() const { return m_animations.isEmpty() && m_transitions.isEmpty() && m_pendingUpdate.isEmpty(); }
+    bool isEmpty() const { return m_runningAnimations.isEmpty() && m_transitions.isEmpty() && m_pendingUpdate.isEmpty(); }
     void cancel();
 
     DECLARE_TRACE();
 
 private:
     class RunningAnimation final : public GarbageCollectedFinalized<RunningAnimation> {
     public:
         RunningAnimation(Animation* animation, CSSAnimationUpdate::NewAnimation newAnimation)
             : animation(animation)
+            , name(newAnimation.name)
+            , nameIndex(newAnimation.nameIndex)
             , specifiedTiming(newAnimation.timing)
             , styleRule(newAnimation.styleRule)
             , styleRuleVersion(newAnimation.styleRuleVersion)
         {
         }
 
         void update(CSSAnimationUpdate::UpdatedAnimation update)
         {
+            ASSERT(update.animation == animation);
             styleRule = update.styleRule;
             styleRuleVersion = update.styleRuleVersion;
             specifiedTiming = update.specifiedTiming;
         }
 
         DEFINE_INLINE_TRACE()
         {
             visitor->trace(animation);
             visitor->trace(styleRule);
         }
 
         Member<Animation> animation;
+        AtomicString name;
+        size_t nameIndex;
         Timing specifiedTiming;
         RefPtrWillBeMember<StyleRuleKeyframes> styleRule;
         unsigned styleRuleVersion;
     };
 
     struct RunningTransition {
         ALLOW_ONLY_INLINE_ALLOCATION();
     public:
         DEFINE_INLINE_TRACE()
         {
             visitor->trace(animation);
         }
 
         Member<Animation> animation;
         const AnimatableValue* from;
         const AnimatableValue* to;
     };
 
-    using AnimationMap = HeapHashMap<AtomicString, Member<RunningAnimation>>;
-    AnimationMap m_animations;
+    HeapVector<Member<RunningAnimation>> m_runningAnimations;
 
     using TransitionMap = HeapHashMap<CSSPropertyID, RunningTransition>;
     TransitionMap m_transitions;
 
     CSSAnimationUpdate m_pendingUpdate;
 
     ActiveInterpolationsMap m_previousActiveInterpolationsForAnimations;
 
     static void calculateCompositorAnimationUpdate(CSSAnimationUpdate&, const Element* animatingElement, Element&, const ComputedStyle&);
     static void calculateAnimationUpdate(CSSAnimationUpdate&, const Element* animatingElement, Element&, const ComputedStyle&, ComputedStyle* parentStyle, StyleResolver*);
@@ skipping 48 matching lines @@
 
         RawPtrWillBeMember<Element> m_transitionTarget;
         const CSSPropertyID m_property;
         AnimationEffect::Phase m_previousPhase;
     };
 };
 
 } // namespace blink
 
 #endif