Fix sticky constraints and update sticky layer positions recursively after scroll.

third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h

 /*
  * Copyright (C) 2003, 2009, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 51 matching lines @@
 class HitTestResult;
 class LayoutBox;
 class LayoutScrollbarPart;
 class PaintLayer;
 class PlatformEvent;
 class StickyPositionScrollingConstraints;
 class SubtreeLayoutScope;
 
 typedef WTF::HashMap<PaintLayer*, StickyPositionScrollingConstraints> StickyConstraintsMap;
 
-struct PaintLayerScrollableAreaRareData {
+struct CORE_EXPORT PaintLayerScrollableAreaRareData {
     WTF_MAKE_NONCOPYABLE(PaintLayerScrollableAreaRareData);
     USING_FAST_MALLOC(PaintLayerScrollableAreaRareData);
 public:
     PaintLayerScrollableAreaRareData();
 
     StickyConstraintsMap m_stickyConstraintsMap;
 };
 
 // PaintLayerScrollableArea represents the scrollable area of a LayoutBox.
 //
@@ skipping 376 matching lines @@
 #endif
 };
 
 DEFINE_TYPE_CASTS(PaintLayerScrollableArea, ScrollableArea, scrollableArea,
     scrollableArea->isPaintLayerScrollableArea(),
     scrollableArea.isPaintLayerScrollableArea());
 
 } // namespace blink
 
 #endif // LayerScrollableArea_h