Bug 30751 [Viewers] Closing all projects doesnt clear package browser list [browsing]
In the java browsing perspective, if you close all projects, the packages browser still has a list of all the packages from the last opened project.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/StructuredViewer.java
*
 * @param element the element
 * @param properties the properties that have changed, or <code>null</code> to indicate unknown
 */
public void update(Object element, String[] properties) {
	Assert.isNotNull(element);
	Widget item = findItem(element);
	if (item == null)
		return;
		
	boolean needsRefilter = false;
	if (properties != null) {
		for (int i = 0; i < properties.length; ++i) {
			needsRefilter = needsRefilter(element, properties[i]);
			if (needsRefilter)
				break;
		}
	}
	if (needsRefilter) {
		refresh();
		return;
	}
	boolean needsUpdate;
	if (properties == null) {
		needsUpdate = true;
	}
	else {
		needsUpdate = false;
		IBaseLabelProvider labelProvider = getLabelProvider();
		for (int i = 0; i < properties.length; ++i) {