Make the timer in SMILTimeContainer more of an implementation detail

Source/core/svg/animation/SMILTimeContainer.h

Index: Source/core/svg/animation/SMILTimeContainer.h
diff --git a/Source/core/svg/animation/SMILTimeContainer.h b/Source/core/svg/animation/SMILTimeContainer.h
index 0aca0ad50444975296b20ef9d2e09e06662ee1d7..bff4ae935b6faaa287b39e1d2914ee0559c475e8 100644
--- a/Source/core/svg/animation/SMILTimeContainer.h
+++ b/Source/core/svg/animation/SMILTimeContainer.h
@@ -66,8 +66,11 @@ public:
 private:
     SMILTimeContainer(SVGSVGElement* owner);
 
+    bool isTimelineRunning() const;
+    void scheduleAnimationFrame(SMILTime fireTime);
+    void scheduleAnimationFrame();
+    void cancelAnimationFrame();
     void timerFired(Timer<SMILTimeContainer>*);
-    void startTimer(SMILTime fireTime, SMILTime minimumDelay = 0);
     void updateAnimations(SMILTime elapsed, bool seekToTime = false);
 
     void updateDocumentOrderIndexes();