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
/**
 * Refreshes this viewer starting with the given element.
 * <p>
 * Unlike the <code>update</code> methods, this handles structural changes
 * to the given element (e.g. addition or removal of children).
 * If only the given element needs updating, it is more efficient to use
 * the <code>update</code> methods.
 * </p>
 *
 * @param element the element
 */
public void refresh(final Object element) {
	preservingSelection(new Runnable() {
		public void run() {
			internalRefresh(element);
		}
	});
}
/**
 * Refreshes this viewer starting with the given element.
 * Labels are updated as described in <code>refresh(boolean updateLabels)</code>.
 * <p>
 * Unlike the <code>update</code> methods, this handles structural changes
 * to the given element (e.g. addition or removal of children).
 * If only the given element needs updating, it is more efficient to use
 * the <code>update</code> methods.
 * </p>
 * 
 * @param element the element
 * @param updateLabels <code>true</code> to update labels for existing elements,