Consistently disable the LayoutState for certain layout situations

Source/core/rendering/RenderObject.h

Index: Source/core/rendering/RenderObject.h
diff --git a/Source/core/rendering/RenderObject.h b/Source/core/rendering/RenderObject.h
index 7fd2dfebb7a2ebf2c8ebef682eeffd473a9b1c3f..6544dcc545c9b701dc0c812d6289fb536a269180 100644
--- a/Source/core/rendering/RenderObject.h
+++ b/Source/core/rendering/RenderObject.h
@@ -981,6 +981,8 @@ public:
     bool layoutDidGetCalled() { return m_bitfields.layoutDidGetCalled(); }
     void setLayoutDidGetCalled(bool b) { m_bitfields.setLayoutDidGetCalled(b); }
 
+    bool shouldDisableLayoutState() const { return hasColumns() || hasTransform() || hasReflection() || style()->isFlippedBlocksWritingMode(); }

[pdr., 2014/02/20 21:19:48]

The comment in RenderEmbeddedObject.cpp makes me think this could be performance
sensitive. I don't think the additional checks for some classes will matter too
much, but it may be useful to declare this as inline.

+
 protected:
     inline bool layerCreationAllowedForSubtree() const;