Oilpan: convert remaining dom + page Element refs to transition types.

Source/core/page/PrintContext.cpp

Index: Source/core/page/PrintContext.cpp
diff --git a/Source/core/page/PrintContext.cpp b/Source/core/page/PrintContext.cpp
index 3eb2a00ce4ff025939b92d5c85d09ade8c57f455..e5373edbaeed30cd9ffd39b810289b37d1484e2f 100644
--- a/Source/core/page/PrintContext.cpp
+++ b/Source/core/page/PrintContext.cpp
@@ -209,7 +209,7 @@ static RenderBoxModelObject* enclosingBoxModelObject(RenderObject* object)
 int PrintContext::pageNumberForElement(Element* element, const FloatSize& pageSizeInPixels)
 {
     // Make sure the element is not freed during the layout.
-    RefPtrWillBeRawPtr<Element> elementRef(element);
+    RefPtrWillBeRawPtr<Element> protect(element);
     element->document().updateLayout();
 
     RenderBoxModelObject* box = enclosingBoxModelObject(element->renderer());