Reduce invalidation on children-needs-layout containers

Source/core/rendering/style/RenderStyle.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *
  * 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
@@ skipping 787 matching lines @@
     LayoutBoxExtent getBoxShadowInsetExtent() const { return getShadowInsetExtent(boxShadow()); }
     void getBoxShadowHorizontalExtent(LayoutUnit& left, LayoutUnit& right) const { getShadowHorizontalExtent(boxShadow(), left, right); }
     void getBoxShadowVerticalExtent(LayoutUnit& top, LayoutUnit& bottom) const { getShadowVerticalExtent(boxShadow(), top, bottom); }
     void getBoxShadowInlineDirectionExtent(LayoutUnit& logicalLeft, LayoutUnit& logicalRight) { getShadowInlineDirectionExtent(boxShadow(), logicalLeft, logicalRight); }
     void getBoxShadowBlockDirectionExtent(LayoutUnit& logicalTop, LayoutUnit& logicalBottom) { getShadowBlockDirectionExtent(boxShadow(), logicalTop, logicalBottom); }
 
     EBoxDecorationBreak boxDecorationBreak() const { return m_box->boxDecorationBreak(); }
     StyleReflection* boxReflect() const { return rareNonInheritedData->m_boxReflect.get(); }
     bool reflectionDataEquivalent(const RenderStyle* otherStyle) const { return rareNonInheritedData->reflectionDataEquivalent(*otherStyle->rareNonInheritedData); }
 
+    bool hasVisualOverflowingEffect() const { return boxShadow() || hasBorderImageOutsets() || hasOutline(); }

[eseidel, 2014/03/21 00:37:09]

Love it.  Reflection?  Presumably this is also only self-painting effects, since
you can have visual/layout overflowing kids who paint of course.

[Julien - ping for review, 2014/03/24 18:00:01]

Currently no renderer knows about reflections as they are handled in
self-painting layers (ie out of the normal overflow tracking logic). Your
suggestion makes total sense but it doesn't work with the current code.

+
     EBoxSizing boxSizing() const { return m_box->boxSizing(); }
     const Length& marqueeIncrement() const { return rareNonInheritedData->m_marquee->increment; }
     int marqueeSpeed() const { return rareNonInheritedData->m_marquee->speed; }
     int marqueeLoopCount() const { return rareNonInheritedData->m_marquee->loops; }
     EMarqueeBehavior marqueeBehavior() const { return static_cast<EMarqueeBehavior>(rareNonInheritedData->m_marquee->behavior); }
     EMarqueeDirection marqueeDirection() const { return static_cast<EMarqueeDirection>(rareNonInheritedData->m_marquee->direction); }
     EUserModify userModify() const { return static_cast<EUserModify>(rareInheritedData->userModify); }
     EUserDrag userDrag() const { return static_cast<EUserDrag>(rareNonInheritedData->userDrag); }
     EUserSelect userSelect() const { return static_cast<EUserSelect>(rareInheritedData->userSelect); }
     TextOverflow textOverflow() const { return static_cast<TextOverflow>(rareNonInheritedData->textOverflow); }
@@ skipping 1065 matching lines @@
 inline bool RenderStyle::hasPseudoElementStyle() const
 {
     return noninherited_flags._pseudoBits & PSEUDO_ELEMENT_MASK;
 }
 
 float calcBorderRadiiConstraintScaleFor(const FloatRect&, const FloatRoundedRect::Radii&);
 
 } // namespace WebCore
 
 #endif // RenderStyle_h