Bug 214621 [Viewers] Make ComboViewer non-final
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ComboViewer.java
* a CCombo control, some kind of unchecked exception is thrown.
	 * 
	 * @return the list control
     * @since 3.3
	 */
    public CCombo getCCombo() {
        Assert.isNotNull(ccombo);
        return ccombo;
    }
    /**
     * Returns this list viewer's list control. If the viewer was not created on
	 * a Combo control, some kind of unchecked exception is thrown.
     *
     * @return the list control
     */
    public Combo getCombo() {
    	Assert.isNotNull(combo);
        return combo;
    }
    
    /*
     * Do nothing -- combos only display the selected element, so there is no way
     * we can ensure that the given element is visible without changing the selection.
     * Method defined on StructuredViewer.
     */
    public void reveal(Object element) {
    }
    
    /* (non-Javadoc)
     * @see org.eclipse.jface.viewers.AbstractListViewer#listSetSelection(int[])