Oilpan: Prepare to move RenderObject and RenderObjectChildList to Oilpan heap.

Source/core/rendering/RenderWidget.h

Index: Source/core/rendering/RenderWidget.h
diff --git a/Source/core/rendering/RenderWidget.h b/Source/core/rendering/RenderWidget.h
index 3c67b19d8e225a9d85071b712ddb4a3e484533d2..b2dd7e578c2ead994f6edfd1ede3d85e26dd2e00 100644
--- a/Source/core/rendering/RenderWidget.h
+++ b/Source/core/rendering/RenderWidget.h
@@ -38,10 +38,10 @@ public:
     void widgetPositionsUpdated();
 
     void setIsOverlapped(bool);
-
+#if !ENABLE(OILPAN)
     void ref() { ++m_refCount; }
     void deref();
-
+#endif
     virtual bool isWidget() const OVERRIDE FINAL { return true; }
     bool updateWidgetGeometry();
 
@@ -61,8 +61,9 @@ private:
     virtual void destroy() OVERRIDE FINAL;
 
     bool setWidgetGeometry(const LayoutRect&);
-
+#if !ENABLE(OILPAN)
     int m_refCount;
+#endif
 };
 
 DEFINE_RENDER_OBJECT_TYPE_CASTS(RenderWidget, isWidget());