Reduce invalidation on children-needs-layout containers

Source/core/rendering/style/RenderStyle.h

Index: Source/core/rendering/style/RenderStyle.h
diff --git a/Source/core/rendering/style/RenderStyle.h b/Source/core/rendering/style/RenderStyle.h
index 75d996f1dc09f361cb62ab61c1a2bd37b5664b5b..e74268db80fed0d479d541aa297310df0b57fa5f 100644
--- a/Source/core/rendering/style/RenderStyle.h
+++ b/Source/core/rendering/style/RenderStyle.h
@@ -805,6 +805,8 @@ public:
     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; }