[Oilpan] Move ScrollAnimators onto oilpan heap

third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.cpp

 /*
  * Copyright (c) 2010, 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 77 matching lines @@
     m_scrollableArea->scrollPositionChanged(DoublePoint(m_currentPosX, m_currentPosY), UserScroll);
 }
 
 float ScrollAnimatorBase::clampScrollPosition(ScrollbarOrientation orientation, float pos)
 {
     float maxScrollPos = m_scrollableArea->maximumScrollPosition(orientation);
     float minScrollPos = m_scrollableArea->minimumScrollPosition(orientation);
     return std::max(std::min(pos, maxScrollPos), minScrollPos);
 }
 
+DEFINE_TRACE(ScrollAnimatorBase)
+{
+    visitor->trace(m_scrollableArea);
+}
+
 } // namespace blink