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
return elementA == null ? elementB == null : elementA.equals(elementB);
		} else {
			return elementA == null ? elementB == null : comparer.equals(elementA, elementB);
		}
	}
	/**
	 * Returns the result of running the given elements through the filters.
	 * 
	 * @param elements
	 *            the elements to filter
	 * @return only the elements which all filters accept
	 */
	protected Object[] filter(Object[] elements) {
		if (filters != null) {
			ArrayList filtered = new ArrayList(elements.length);
			Object root = getRoot();
			for (int i = 0; i < elements.length; i++) {
				boolean add = true;
				for (int j = 0; j < filters.size(); j++) {
					add = ((ViewerFilter) filters.get(j)).select(this, root, elements[i]);
					if (!add) {
						break;
					}
				}
				if (add) {
					filtered.add(elements[i]);
				}
			}
			return filtered.toArray();
		}