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 listener a double-click listener
 */
public void removeOpenListener(IOpenListener listener) {
	openListeners.remove(listener);
}
/**
 * Removes the given post selection listener from this viewer.
 * Has no affect if an identical listener is not registered.
 *
 * @param listener a double-click listener
 */
public void removePostSelectionChangedListener(ISelectionChangedListener listener) {
	postSelectionChangedListeners.remove(listener);
}
/**
 * Removes the given double-click listener from this viewer.
 * Has no affect if an identical listener is not registered.
 *
 * @param listener a double-click listener
 */
public void removeDoubleClickListener(IDoubleClickListener listener) {
	doubleClickListeners.remove(listener);
}
/**
 * Removes the given filter from this viewer, 
 * and triggers refiltering and resorting of the elements if required.
 * Has no effect if the identical filter is not registered.
 *
 * @param filter a viewer filter
 */