Implement SANACLAP (http://bit.ly/sanaclap).

third_party/WebKit/Source/core/style/ComputedStyle.cpp

 /*
  * Copyright (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2011 Adobe Systems Incorporated. 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 485 matching lines @@
             diff.setNeedsPositionedMovementLayout();
     }
 
     if (diffNeedsPaintInvalidationSubtree(other))
         diff.setNeedsPaintInvalidationSubtree();
     else if (diffNeedsPaintInvalidationObject(other))
         diff.setNeedsPaintInvalidationObject();
 
     updatePropertySpecificDifferences(other, diff);
 
+    // TODO(skobes): Refine the criteria for ScrollAnchor-disabling properties.
+    // Some things set needsLayout but shouldn't disable scroll anchoring.
+    if (diff.needsLayout() || diff.transformChanged())
+        diff.setScrollAnchorDisablingPropertyChanged();
+
     // Cursors are not checked, since they will be set appropriately in response to mouse events,
     // so they don't need to cause any paint invalidation or layout.
 
     // Animations don't need to be checked either. We always set the new style on the layoutObject, so we will get a chance to fire off
     // the resulting transition properly.
 
     return diff;
 }
 
 bool ComputedStyle::diffNeedsFullLayoutAndPaintInvalidation(const ComputedStyle& other) const
@@ skipping 1450 matching lines @@
         if (value < 0)
             fvalue -= 0.5f;
         else
             fvalue += 0.5f;
     }
 
     return roundForImpreciseConversion<int>(fvalue / zoomFactor);
 }
 
 } // namespace blink