Add operator== to CSSAnimationData.

third_party/WebKit/Source/core/animation/css/CSSAnimationData.h

Index: third_party/WebKit/Source/core/animation/css/CSSAnimationData.h
diff --git a/third_party/WebKit/Source/core/animation/css/CSSAnimationData.h b/third_party/WebKit/Source/core/animation/css/CSSAnimationData.h
index f8ee8c3c1e014e545ccd45bc300e2bea584e8edd..c49ec6cdcd21402c15483c926d61b792c483758a 100644
--- a/third_party/WebKit/Source/core/animation/css/CSSAnimationData.h
+++ b/third_party/WebKit/Source/core/animation/css/CSSAnimationData.h
@@ -24,6 +24,9 @@ class CSSAnimationData final : public CSSTimingData {
   }
 
   bool AnimationsMatchForStyleRecalc(const CSSAnimationData& other) const;
+  bool operator==(const CSSAnimationData& other) const {
+    return AnimationsMatchForStyleRecalc(other);
+  }
 
   Timing ConvertToTiming(size_t index) const;