Introduce HTMLDataListOptionsCollection subclass for HTMLCollection

Source/core/html/HTMLDataListElement.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2010 Apple 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 18 matching lines @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "core/html/HTMLDataListElement.h"
 
 #include "core/HTMLNames.h"
 #include "core/dom/IdTargetObserverRegistry.h"
 #include "core/dom/NodeListsNodeData.h"
 #include "core/frame/UseCounter.h"
+#include "core/html/HTMLDataListOptionsCollection.h"
 
 namespace blink {
 
 inline HTMLDataListElement::HTMLDataListElement(Document& document)
     : HTMLElement(HTMLNames::datalistTag, document)
 {
     ScriptWrappable::init(this);
 }
 
 PassRefPtrWillBeRawPtr<HTMLDataListElement> HTMLDataListElement::create(Document& document)
 {
     UseCounter::count(document, UseCounter::DataListElement);
     return adoptRefWillBeNoop(new HTMLDataListElement(document));
 }
 
-PassRefPtrWillBeRawPtr<HTMLCollection> HTMLDataListElement::options()
+PassRefPtrWillBeRawPtr<HTMLDataListOptionsCollection> HTMLDataListElement::options()
 {
-    return ensureCachedCollection<HTMLCollection>(DataListOptions);
+    return ensureCachedCollection<HTMLDataListOptionsCollection>(DataListOptions);
 }
 
 void HTMLDataListElement::childrenChanged(const ChildrenChange& change)
 {
     HTMLElement::childrenChanged(change);
     if (!change.byParser)
         treeScope().idTargetObserverRegistry().notifyObservers(getIdAttribute());
 }
 
 void HTMLDataListElement::finishParsingChildren()
 {
     treeScope().idTargetObserverRegistry().notifyObservers(getIdAttribute());
 }
 
 void HTMLDataListElement::optionElementChildrenChanged()
 {
     treeScope().idTargetObserverRegistry().notifyObservers(getIdAttribute());
 }
 
 } // namespace blink