Update ScrollAnimator's copy of the layer dimensions after layout.

Source/platform/scroll/ScrollAnimatorNone.cpp

 /*
  * Copyright (c) 2011, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 448 matching lines @@
 {
     if (m_animationActive)
         animationTimerFired();
 }
 
 bool ScrollAnimatorNone::hasRunningAnimation() const
 {
     return m_animationActive;
 }
 
+void ScrollAnimatorNone::updateAfterLayout()
+{
+    updateVisibleLengths();
+}
+
 void ScrollAnimatorNone::willEndLiveResize()
 {
     updateVisibleLengths();
 }
 
 void ScrollAnimatorNone::didAddVerticalScrollbar(Scrollbar*)
 {
     updateVisibleLengths();
 }
 
@@ skipping 43 matching lines @@
     return m_animationActive;
 }
 
 void ScrollAnimatorNone::stopAnimationTimerIfNeeded()
 {
     if (animationTimerActive())
         m_animationActive = false;
 }
 
 } // namespace blink