Fix invalidation during painting of scrollbars

Source/core/layout/LayoutBox.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2006, 2007 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 139 matching lines @@
             setWidth(size);
     }
 
     LayoutPoint location() const { return m_frameRect.location(); }
     LayoutSize locationOffset() const { return LayoutSize(m_frameRect.x(), m_frameRect.y()); }
     LayoutSize size() const { return m_frameRect.size(); }
     IntSize pixelSnappedSize() const { return m_frameRect.pixelSnappedSize(); }
 
     void setLocation(const LayoutPoint& location) { m_frameRect.setLocation(location); }
 
+    // FIXME: Currently scrollbars are using int geometry and positioned based on
+    // pixelSnappedBorderBoxRect whose size may change when location changes because of
+    // pixel snapping. This function is used to change location of the RenderBox outside
+    // of RenderBox::layout(). Will remove when we use LayoutUnits for scrollbars.
+    void setLocationAndUpdateOverflowControlsIfNeeded(const LayoutPoint&);
+
     void setSize(const LayoutSize& size) { m_frameRect.setSize(size); }
     void move(LayoutUnit dx, LayoutUnit dy) { m_frameRect.move(dx, dy); }
 
     LayoutRect frameRect() const { return m_frameRect; }
     void setFrameRect(const LayoutRect& rect) { m_frameRect = rect; }
 
     LayoutRect borderBoxRect() const { return LayoutRect(LayoutPoint(), size()); }
     LayoutRect paddingBoxRect() const { return LayoutRect(borderLeft(), borderTop(), clientWidth(), clientHeight()); }
     IntRect pixelSnappedBorderBoxRect() const { return IntRect(IntPoint(), m_frameRect.pixelSnappedSize()); }
     virtual IntRect borderBoundingBox() const override final { return pixelSnappedBorderBoxRect(); }
@@ skipping 680 matching lines @@
         if (UNLIKELY(inlineBoxWrapper() != 0))
             deleteLineBoxWrapper();
     }
 
     ensureRareData().m_inlineBoxWrapper = boxWrapper;
 }
 
 } // namespace blink
 
 #endif // LayoutBox_h