Pass implementation object to supplemental classes by reference

Source/core/xml/DocumentXPathEvaluator.h

Index: Source/core/xml/DocumentXPathEvaluator.h
diff --git a/Source/core/xml/DocumentXPathEvaluator.h b/Source/core/xml/DocumentXPathEvaluator.h
index afece8d257941b2f8b17c9624cdd2251a2aa0ed8..d08c58ae7c640dc6ed2e47a18ff1ea2d02951600 100644
--- a/Source/core/xml/DocumentXPathEvaluator.h
+++ b/Source/core/xml/DocumentXPathEvaluator.h
@@ -40,12 +40,12 @@ class DocumentXPathEvaluator FINAL : public DocumentSupplement {
 public:
     virtual ~DocumentXPathEvaluator();
 
-    static DocumentXPathEvaluator* from(DocumentSupplementable*);
+    static DocumentXPathEvaluator& from(DocumentSupplementable&);
 
-    static PassRefPtrWillBeRawPtr<XPathExpression> createExpression(DocumentSupplementable*,
+    static PassRefPtrWillBeRawPtr<XPathExpression> createExpression(DocumentSupplementable&,
         const String& expression, PassRefPtrWillBeRawPtr<XPathNSResolver>, ExceptionState&);
-    static PassRefPtrWillBeRawPtr<XPathNSResolver> createNSResolver(DocumentSupplementable*, Node* nodeResolver);
-    static PassRefPtrWillBeRawPtr<XPathResult> evaluate(DocumentSupplementable*,
+    static PassRefPtrWillBeRawPtr<XPathNSResolver> createNSResolver(DocumentSupplementable&, Node* nodeResolver);
+    static PassRefPtrWillBeRawPtr<XPathResult> evaluate(DocumentSupplementable&,
         const String& expression, Node* contextNode, PassRefPtrWillBeRawPtr<XPathNSResolver>,
         unsigned short type, XPathResult*, ExceptionState&);