Have HTMLCollection::item() return an Element as per specification

Source/core/html/HTMLSelectElement.idl

Index: Source/core/html/HTMLSelectElement.idl
diff --git a/Source/core/html/HTMLSelectElement.idl b/Source/core/html/HTMLSelectElement.idl
index d27b2407ac7b23772ee3a01f7e6a48345bda3615..3104a3fdbbc15093e1892ea582d4b79b666d5724 100644
--- a/Source/core/html/HTMLSelectElement.idl
+++ b/Source/core/html/HTMLSelectElement.idl
@@ -33,9 +33,9 @@ interface HTMLSelectElement : HTMLElement {
     readonly attribute HTMLOptionsCollection options;
     [RaisesException=Setter] attribute unsigned long length;
 
-    getter Node item(unsigned long index);
+    getter Element item(unsigned long index);
     [RaisesException, StrictTypeChecking] setter HTMLOptionElement (unsigned long index, HTMLOptionElement? value);
-    Node namedItem([Default=Undefined] optional DOMString name);
+    Element namedItem([Default=Undefined] optional DOMString name);
     [RaisesException] void add([Default=Undefined] optional HTMLElement element,
                                [Default=Undefined] optional HTMLElement before);
     void remove(long index);