Sync the HTMLCollection interfaces with the specs

Source/core/html/HTMLOptionsCollection.idl

Index: Source/core/html/HTMLOptionsCollection.idl
diff --git a/Source/core/html/HTMLOptionsCollection.idl b/Source/core/html/HTMLOptionsCollection.idl
index f17973199830762a3172645fa4723f8f4b63a9b9..f5840306c3361f676c537436ab741caa766b2db0 100644
--- a/Source/core/html/HTMLOptionsCollection.idl
+++ b/Source/core/html/HTMLOptionsCollection.idl
@@ -19,19 +19,22 @@
  * Boston, MA 02110-1301, USA.
  */
 
+// https://html.spec.whatwg.org/#the-htmloptionscollection-interface
+
 [
     DependentLifetime,
     SetWrapperReferenceFrom=ownerNode,
 ] interface HTMLOptionsCollection : HTMLCollection {
+    // inherits item()
+    [Custom=Setter, RaisesException=Setter] attribute unsigned long length; // shadows inherited length
+    // FIXME: The spec has a legacycaller HTMLOptionElement? (DOMString name);
+    [RaisesException, TypeChecking=Interface] setter void (unsigned long index, HTMLOptionElement? option);
+    [RaisesException, TypeChecking=Interface] void add((HTMLOptionElement or HTMLOptGroupElement) element, optional (HTMLElement or long)? before = null);
+    // FIXME: the index argument should be long, not unsigned long.
+    void remove(unsigned long index);
     attribute long selectedIndex;
-    [Custom=Setter, RaisesException=Setter] attribute unsigned long length;
+    // FIXME: Neither of these getters are in the spec, and the
+    // getters inherited from HTMLCollection always return an Element.
     [ImplementedAs=item] getter Node (unsigned long index);
-    [RaisesException, TypeChecking=Interface] setter HTMLOptionElement (unsigned long index, HTMLOptionElement? value);
-
-    // FIXME: The spec and firefox return an Element (the first matching Element).
     [ImplementedAs=namedGetter] getter (NodeList or Element)? namedItem(DOMString name);
-
-    [RaisesException, TypeChecking=Interface] void add((HTMLOptionElement or HTMLOptGroupElement) element,
-                                                       optional (HTMLElement or long)? before = null);
-    void remove(unsigned long index);
 };