Bug 88993 [Viewers] CCE in AbstractTreeViewer.indexForElement(..)
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
Widget w = internalExpand(v.get(i), true);
            if (w instanceof Item) {
                newSelection.add(w);
            }
        }
        setSelection(newSelection);
        if (reveal && newSelection.size() > 0) {
            showItem((Item) newSelection.get(0));
        }
    }
    /**
     * Shows the given item.
     * 
     * @param item
     *           the item
     */
    protected abstract void showItem(Item item);
    /**
     * Updates the tree items to correspond to the child elements of the given
     * parent element. If null is passed for the children, this method obtains
     * them (only if needed).
     * 
     * @param widget
     *           the widget
     * @param parent
     *           the parent element
     * @param elementChildren
     *           the child elements, or null