Adding or changing any of box-shadow, outline, or border-image-outset does not need a layout..

third_party/WebKit/Source/core/layout/LayoutObject.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google 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
@@ skipping 1378 matching lines @@
         MutableForPainting(const LayoutObject& layoutObject) : m_layoutObject(const_cast<LayoutObject&>(layoutObject)) { }
 
         LayoutObject& m_layoutObject;
     };
     MutableForPainting getMutableForPainting() const { return MutableForPainting(*this); }
 
     void setIsScrollAnchorObject() { m_bitfields.setIsScrollAnchorObject(true); }
     // Clears the IsScrollAnchorObject bit, unless any ScrollAnchor still refers to us.
     void maybeClearIsScrollAnchorObject();
 
+    void clearChildNeedsOverflowRecalcAfterStyleChange() { m_bitfields.setChildNeedsOverflowRecalcAfterStyleChange(false); }
+
 protected:
     enum LayoutObjectType {
         LayoutObjectBr,
         LayoutObjectCanvas,
         LayoutObjectFieldset,
         LayoutObjectCounter,
         LayoutObjectDetailsMarker,
         LayoutObjectEmbeddedObject,
         LayoutObjectFileUploadControl,
         LayoutObjectFrame,
@@ skipping 152 matching lines @@
     // The caller should ensure the enclosing layer has been setNeedsRepaint before calling this function.
     virtual void invalidateDisplayItemClients(const LayoutBoxModelObject& paintInvalidationContainer, PaintInvalidationReason) const;
 
     // Sets enclosing layer needsRepaint, then calls invalidateDisplayItemClients().
     // Should use this version when PaintInvalidationState is available.
     void invalidateDisplayItemClientsWithPaintInvalidationState(const LayoutBoxModelObject& paintInvalidationContainer, const PaintInvalidationState&, PaintInvalidationReason) const;
 
     void setIsBackgroundAttachmentFixedObject(bool);
 
     void clearSelfNeedsOverflowRecalcAfterStyleChange() { m_bitfields.setSelfNeedsOverflowRecalcAfterStyleChange(false); }
-    void clearChildNeedsOverflowRecalcAfterStyleChange() { m_bitfields.setChildNeedsOverflowRecalcAfterStyleChange(false); }
     void setShouldInvalidateOverflowForPaint() { m_bitfields.setShouldInvalidateOverflowForPaint(true); }
     void setEverHadLayout() { m_bitfields.setEverHadLayout(true); }
 
     // Remove this object and all descendants from the containing LayoutFlowThread.
     void removeFromLayoutFlowThread();
 
     bool containsInlineWithOutlineAndContinuation() const { return m_bitfields.containsInlineWithOutlineAndContinuation(); }
     void setContainsInlineWithOutlineAndContinuation(bool b) { m_bitfields.setContainsInlineWithOutlineAndContinuation(b); }
 
     const LayoutRect& previousPaintInvalidationRect() const { return m_previousPaintInvalidationRect; }
@@ skipping 21 matching lines @@
 
     void updateShapeImage(const ShapeValue*, const ShapeValue*);
     void updateFillImages(const FillLayer* oldLayers, const FillLayer& newLayers);
 
     void setNeedsOverflowRecalcAfterStyleChange();
 
     void markContainerChainForLayout(bool scheduleRelayout, SubtreeLayoutScope*);
 
     // FIXME: This should be 'markContaingBoxChainForOverflowRecalc when we make LayoutBox
     // recomputeOverflow-capable. crbug.com/437012 and crbug.com/434700.
-    inline void markContainingBlocksForOverflowRecalc();
+    inline void markAncestorsForOverflowRecalcIfNeeded();
 
     inline void markAncestorsForPaintInvalidation();
 
     inline void invalidateSelectionIfNeeded(const LayoutBoxModelObject& paintInvalidationContainer, const PaintInvalidationState&, PaintInvalidationReason);
 
     inline void invalidateContainerPreferredLogicalWidths();
 
     void invalidatePaintIncludingNonSelfPaintingLayerDescendantsInternal(const LayoutBoxModelObject& paintInvalidationContainer);
 
     // The caller should ensure the enclosing layer has been setNeedsRepaint before calling this function.
@@ skipping 550 matching lines @@
 void showTree(const blink::LayoutObject*);
 void showLineTree(const blink::LayoutObject*);
 void showLayoutTree(const blink::LayoutObject* object1);
 // We don't make object2 an optional parameter so that showLayoutTree
 // can be called from gdb easily.
 void showLayoutTree(const blink::LayoutObject* object1, const blink::LayoutObject* object2);
 
 #endif
 
 #endif // LayoutObject_h