Bug 239945 [Coolbar] ArrayIndexOutOfBoundsException -1 in CoolBarManager.update
bundles/org.eclipse.jface/src/org/eclipse/jface/action/CoolBarManager.java
*            the list iterator of contribution items
     * @param ignoreCurrentItem
     *            Whether the current item in the iterator should be considered
     *            (as well as subsequent items).
     */
    private void nextRow(ListIterator iterator, boolean ignoreCurrentItem) {
        IContributionItem currentElement = null;
        if (!ignoreCurrentItem && iterator.hasPrevious()) {
            currentElement = (IContributionItem) iterator.previous();
            iterator.next();
        }
        if ((currentElement != null) && (currentElement.isSeparator())) {
            collapseSeparators(iterator);
            return;
        } 
        
        while (iterator.hasNext()) {
            IContributionItem item = (IContributionItem) iterator.next();
            if (item.isSeparator()) {
                
                
                
                collapseSeparators(iterator);
                return;
            }
        }
    }
    /*
     * Used for debuging. Prints all the items in the internal structures.
     */