Options can not be removed from a Select element with OptGroup's using JavaScript

[diovieno@perseus..com]

If you have a select element as follows

<select name="S1" id="S1">
    <optgroup label="Group 1">
      <option value="1">Option 1</option>
      <option value="2">Option 2</option>
      <option value="3">Option 3</option>
      <option value="4">Option 4</option>
    </optgroup>
    <optgroup label="Group 2">
      <option value="5">Option 5</option>
      <option value="6">Option 6</option>
      <option value="7">Option 7</option>
      <option value="8">Option 8</option>
      <option value="9">Option 9</option>
    </optgroup>
</select>

And attempt to use JavaScript to remove an option from the list

var list = document.getElementById("S1");
list.options[3] = null;
or
list.remove(3);

The item is not removed from the list.
No errors appear in the JavaScript Console.

If the select element does not contain optgroup's, the JavaScript works correctly.

[Alexey Proskuryakov]

Created attachment 16320 [details]
test case

Same test as an attachment.

[Alexey Proskuryakov]

Confirmed with shipping 10.4.10 WebKit and with r25449.

[Rob Buis]

Created attachment 16326 [details]
First attempt

This fixes it and doesn't regress otherwise :)
Cheers,

Rob.

Comment on attachment 16326 [details]
First attempt

r=me

[David Kilzer (:ddkilzer)]

Committed by rwlbuis  in r25668.

http://trac.webkit.org/projects/webkit/changeset/25668

Does this need a radar?

[David Kilzer (:ddkilzer)]

<rdar://problem/5494123>