Web Animations: Trigger and update CSS Animations backed by the Web Animations model

Source/core/animation/Player.h

Index: Source/core/animation/Player.h
diff --git a/Source/core/animation/Player.h b/Source/core/animation/Player.h
index 3b4e480536e39ae27a751e5c6e5fb71c7310ec3b..985fb45c32e5b4d3c7f6b80c692dc0f4487c59b8 100644
--- a/Source/core/animation/Player.h
+++ b/Source/core/animation/Player.h
@@ -46,6 +46,7 @@ public:
 
     // Returns whether this player is still current or in effect.
     bool update();
+    void cancel();
     double currentTime() const;
     void setCurrentTime(double);
     bool paused() const { return !isNull(m_pauseStartTime); }