Have NodeList::item() overrides return an Element* when appropriate

Source/core/html/RadioNodeList.cpp

 /*
  * Copyright (c) 2012 Motorola Mobility, Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 34 matching lines @@
     ScriptWrappable::init(this);
 }
 
 RadioNodeList::~RadioNodeList()
 {
 #if !ENABLE(OILPAN)
     ownerNode().nodeLists()->removeCache(this, m_onlyMatchImgElements ? RadioImgNodeListType : RadioNodeListType, m_name);
 #endif
 }
 
-static inline HTMLInputElement* toRadioButtonInputElement(Node& node)
+static inline HTMLInputElement* toRadioButtonInputElement(Element& element)
 {
-    ASSERT(node.isElementNode());
-    if (!isHTMLInputElement(node))
+    if (!isHTMLInputElement(element))
         return 0;
-    HTMLInputElement& inputElement = toHTMLInputElement(node);
+    HTMLInputElement& inputElement = toHTMLInputElement(element);
     if (!inputElement.isRadioButton() || inputElement.value().isEmpty())
         return 0;
     return &inputElement;
 }
 
 String RadioNodeList::value() const
 {
     if (m_onlyMatchImgElements)
         return String();
-    for (unsigned i = 0; i < length(); ++i) {
-        Node* node = item(i);
-        const HTMLInputElement* inputElement = toRadioButtonInputElement(*node);
+    unsigned length = this->length();
+    for (unsigned i = 0; i < length; ++i) {
+        const HTMLInputElement* inputElement = toRadioButtonInputElement(*item(i));
         if (!inputElement || !inputElement->checked())
             continue;
         return inputElement->value();
     }
     return String();
 }
 
 void RadioNodeList::setValue(const String& value)
 {
     if (m_onlyMatchImgElements)
         return;
-    for (unsigned i = 0; i < length(); ++i) {
-        Node* node = item(i);
-        HTMLInputElement* inputElement = toRadioButtonInputElement(*node);
+    unsigned length = this->length();
+    for (unsigned i = 0; i < length; ++i) {
+        HTMLInputElement* inputElement = toRadioButtonInputElement(*item(i));
         if (!inputElement || inputElement->value() != value)
             continue;
         inputElement->setChecked(true);
         return;
     }
 }
 
 bool RadioNodeList::checkElementMatchesRadioNodeListFilter(const Element& testElement) const
 {
     ASSERT(!m_onlyMatchImgElements);
@@ skipping 16 matching lines @@
         return false;
 
     if (isHTMLInputElement(element) && toHTMLInputElement(element).isImageButton())
         return false;
 
     return checkElementMatchesRadioNodeListFilter(element);
 }
 
 } // namespace