Use the Document AnimationClock in SMILTimeContainer

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 e5518080797b63c2b020d4caebf1c2cbecd2f5b1..84925746f63cdf17080a2b70737b22177b1c4cae 100644
--- a/Source/core/svg/animation/SMILTimeContainer.h
+++ b/Source/core/svg/animation/SMILTimeContainer.h
@@ -38,7 +38,6 @@
 
 namespace WebCore {
 
-class AnimationClock;
 class Document;
 class SVGElement;
 class SVGSMILElement;
@@ -96,7 +95,6 @@ private:
     double lastResumeTime() const { return m_resumeTime ? m_resumeTime : m_beginTime; }
 
     Document& document() const;
-    AnimationClock& animationClock() const;
     double currentTime() const;
 
     double m_beginTime;
@@ -108,7 +106,6 @@ private:
     FrameSchedulingState m_frameSchedulingState;
     bool m_documentOrderIndexesDirty;
 
-    OwnPtr<AnimationClock> m_animationClock;
     Timer<SMILTimeContainer> m_wakeupTimer;
 
     typedef pair<SVGElement*, QualifiedName> ElementAttributePair;