[bindings] Avoid using custom binding for HTMLOptionsCollection.length attribute

Source/core/html/HTMLOptionsCollection.cpp

 /*
  * Copyright (C) 2006, 2011, 2012 Apple Computer, Inc.
  * Copyright (C) 2014 Samsung Electronics. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 73 matching lines @@
     return toHTMLSelectElement(ownerNode()).selectedIndex();
 }
 
 void HTMLOptionsCollection::setSelectedIndex(int index)
 {
     toHTMLSelectElement(ownerNode()).setSelectedIndex(index);
 }
 
 void HTMLOptionsCollection::setLength(unsigned length, ExceptionState& exceptionState)
 {
+    if (length > HTMLSelectElement::maxSelectItems)
+        return;

[tkent, 2015/08/19 01:20:24]

It's inconsistent with the current behavior of HTMLSelectElement::length setter,
which clamps on the value to maxSelectItems.

Does Firefox still have the limitation of the number of items?  If so, how does
it work for length setters?

     toHTMLSelectElement(ownerNode()).setLength(length, exceptionState);
 }
 
 void HTMLOptionsCollection::namedGetter(const AtomicString& name, NodeListOrElement& returnValue)
 {
     WillBeHeapVector<RefPtrWillBeMember<Element>> namedItems;
     this->namedItems(name, namedItems);
 
     if (!namedItems.size())
         return;
@@ skipping 13 matching lines @@
     if (!value) { // undefined or null
         base.remove(index);
         return true;
     }
     base.setOption(index, value.get(), exceptionState);
     return true;
 }
 
 } // namespace