Invalidate background-attachment:fixed on scroll.

third_party/WebKit/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 817 matching lines @@
     {
         // The frame rect may change because of layout of other objects.
         // Should check this object for paint invalidation.
         if (!needsLayout())
             setMayNeedPaintInvalidation();
     }
 
     // Returns true if the box intersects the viewport visible to the user.
     bool intersectsVisibleViewport();
 
-    void updateSlowRepaintStatusAfterStyleChange();
+    void updateBackgroundAttachmentFixedStatusAfterStyleChange();
 
     // The width/height of the contents + borders + padding.  The x/y location is relative to our container (which is not always our parent).
     LayoutRect m_frameRect;
 
     // Our intrinsic height, used for min-height: min-content etc. Maintained by
     // updateLogicalHeight. This is logicalHeight() before it is clamped to
     // min/max.
     mutable LayoutUnit m_intrinsicContentLogicalHeight;
 
     void inflatePaintInvalidationRectForReflectionAndFilter(LayoutRect&) const;
@@ skipping 88 matching lines @@
         if (UNLIKELY(inlineBoxWrapper() != nullptr))
             deleteLineBoxWrapper();
     }
 
     ensureRareData().m_inlineBoxWrapper = boxWrapper;
 }
 
 } // namespace blink
 
 #endif // LayoutBox_h