Web Animations: Add a name to AnimationNode and trace running players

Source/core/animation/AnimationPlayer.h

Index: Source/core/animation/AnimationPlayer.h
diff --git a/Source/core/animation/AnimationPlayer.h b/Source/core/animation/AnimationPlayer.h
index e987097d1c611a93a6dbb23a94cb622ab74946d6..4ed4f1366c793e21a48d6f7932df7f3afc1f35d7 100644
--- a/Source/core/animation/AnimationPlayer.h
+++ b/Source/core/animation/AnimationPlayer.h
@@ -164,6 +164,8 @@ private:
     bool limited(double currentTime) const;
     void updateCurrentTimingState(TimingUpdateReason);
     void unpauseInternal();
+    void uncancel();
+    void setFinished(bool);
 
     double m_playbackRate;
 
@@ -212,16 +214,6 @@ private:
         CompositorAction pendingAction;
     };
 
-    void uncancel()
-    {
-        if (m_idle) {
-            m_idle = false;
-            m_finished = false;
-            m_held = true;
-            m_holdTime = 0;
-        }
-    }
-
     // This mirrors the known compositor state. It is created when a compositor
     // animation is started. Updated once the start time is known and each time
     // modifications are pushed to the compositor.