Bug 299438 [CommonNavigator] CNF viewer state non properly reset when NCEs are activated or deactivated
The map of the objects to the NCEs should be reset whenever the NCEs associated with the viewer to change to avoid having stale label information. This has shown up when looking at the CNF tests that change the viewer.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/StructuredViewer.java
if (mayExitEarly && refreshOccurred) {
				 
				return;
			}
		}		
	}
	/**
     * Updates the given element's presentation when one or more of its
     * properties changes. Only the given element is updated.
     * <p>
     * EXPERIMENTAL.  Not to be used except by JDT.
     * This method was added to support JDT's explorations
     * into grouping by working sets, which requires viewers to support multiple 
     * equal elements.  See bug 76482 for more details.  This support will
     * likely be removed in Eclipse 3.3 in favor of proper support for
     * multiple equal elements (which was implemented for AbtractTreeViewer in 3.2). 
     * </p>
     * @param widget
     *            the widget for the element
     * @param element
     *            the element
     * @param properties
     *            the properties that have changed, or <code>null</code> to
     *            indicate unknown
     */
	protected void internalUpdate(Widget widget, Object element, String[] properties) {
		boolean needsRefilter = false;
		if (properties != null) {
			for (int i = 0; i < properties.length; ++i) {
				needsRefilter = needsRefilter(element, properties[i]);