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

third_party/WebKit/Source/core/page/scrolling/StickyPositionScrollingConstraints.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef StickyPositionScrollingConstraints_h
 #define StickyPositionScrollingConstraints_h
 
 #include "platform/geometry/FloatRect.h"
 
 namespace blink {
 
+class LayoutBoxModelObjectTest;
+
 class StickyPositionScrollingConstraints final {
 public:
     enum AnchorEdgeFlags {
         AnchorEdgeLeft = 1 << 0,
         AnchorEdgeRight = 1 << 1,
         AnchorEdgeTop = 1 << 2,
         AnchorEdgeBottom = 1 << 3
     };
     typedef unsigned AnchorEdges;
 
@@ skipping 42 matching lines @@
             && m_rightOffset == other.m_rightOffset
             && m_topOffset == other.m_topOffset
             && m_bottomOffset == other.m_bottomOffset
             && m_scrollContainerRelativeContainingBlockRect == other.m_scrollContainerRelativeContainingBlockRect
             && m_scrollContainerRelativeStickyBoxRect == other.m_scrollContainerRelativeStickyBoxRect;
     }
 
     bool operator!=(const StickyPositionScrollingConstraints& other) const { return !(*this == other); }
 
 private:
+    friend class LayoutBoxModelObjectTest;
+
+    const FloatRect& scrollContainerRelativeContainingBlockRect() const { return m_scrollContainerRelativeContainingBlockRect; }
+    const FloatRect& scrollContainerRelativeStickyBoxRect() const { return m_scrollContainerRelativeStickyBoxRect; }
+
     AnchorEdges m_anchorEdges;
     float m_leftOffset;
     float m_rightOffset;
     float m_topOffset;
     float m_bottomOffset;
     FloatRect m_scrollContainerRelativeContainingBlockRect;
     FloatRect m_scrollContainerRelativeStickyBoxRect;
 };
 
 } // namespace blink
 
 #endif // StickyPositionScrollingConstraints_h