Update animation when changes in animation keyframes are detected.

Source/core/css/CSSKeyframeRule.h

Index: Source/core/css/CSSKeyframeRule.h
diff --git a/Source/core/css/CSSKeyframeRule.h b/Source/core/css/CSSKeyframeRule.h
index edbdacb572c197ef2af9259477c533522b870e73..e07ac1b689aabc0e969e56e99d8c943343ca988d 100644
--- a/Source/core/css/CSSKeyframeRule.h
+++ b/Source/core/css/CSSKeyframeRule.h
@@ -34,7 +34,7 @@ namespace blink {
 class CSSKeyframesRule;
 class CSSStyleDeclaration;
 class ExceptionState;
-class StyleRuleCSSStyleDeclaration;
+class KeyframeStyleRuleCSSStyleDeclaration;
 
 class CSSKeyframeRule final : public CSSRule {
     DEFINE_WRAPPERTYPEINFO();
@@ -57,7 +57,7 @@ private:
     virtual CSSRule::Type type() const override { return KEYFRAME_RULE; }
 
     RefPtrWillBeMember<StyleRuleKeyframe> m_keyframe;
-    mutable RefPtrWillBeMember<StyleRuleCSSStyleDeclaration> m_propertiesCSSOMWrapper;
+    mutable RefPtrWillBeMember<KeyframeStyleRuleCSSStyleDeclaration> m_propertiesCSSOMWrapper;
 
     friend class CSSKeyframesRule;
 };