Move LayoutBoxModelObject's PaintLayer member to rare paint data

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

Index: third_party/WebKit/Source/core/layout/LayoutObject.h
diff --git a/third_party/WebKit/Source/core/layout/LayoutObject.h b/third_party/WebKit/Source/core/layout/LayoutObject.h
index d1d382e325d830968c10971c48ae0237a87206c3..e1b9f500e9d4752b0dbfbaf93a3988cca740fe7b 100644
--- a/third_party/WebKit/Source/core/layout/LayoutObject.h
+++ b/third_party/WebKit/Source/core/layout/LayoutObject.h
@@ -417,9 +417,6 @@ class CORE_EXPORT LayoutObject : public ImageResourceObserver,
   PropertyTreeState ContentsProperties() const;
 
  private:
-  RarePaintData& EnsureRarePaintData();
-  RarePaintData* GetRarePaintData() { return rare_paint_data_.get(); }
-
   //////////////////////////////////////////
   // Helper functions. Dangerous to use!
   void SetPreviousSibling(LayoutObject* previous) { previous_ = previous; }
@@ -2108,6 +2105,9 @@ class CORE_EXPORT LayoutObject : public ImageResourceObserver,
     bitfields_.SetPreviousOutlineMayBeAffectedByDescendants(b);
   }
 
+  RarePaintData& EnsureRarePaintData();
+  RarePaintData* GetRarePaintData() const { return rare_paint_data_.get(); }
+
  private:
   // Used only by applyFirstLineChanges to get a first line style based off of a
   // given new style, without accessing the cache.