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
import java.util.List;
import org.eclipse.core.runtime.Platform;
import org.eclipse.swt.dnd.DragSource;
import org.eclipse.swt.dnd.DragSourceListener;
import org.eclipse.swt.dnd.DropTarget;
import org.eclipse.swt.dnd.DropTargetListener;
import org.eclipse.swt.dnd.Transfer;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Item;
import org.eclipse.swt.widgets.Widget;
import org.eclipse.jface.util.Assert;
import org.eclipse.jface.util.IOpenEventListener;
import org.eclipse.jface.util.ListenerList;
import org.eclipse.jface.util.OpenStrategy;
import org.eclipse.jface.util.SafeRunnable;
/**
 * Abstract base implementation for structure-oriented viewers (trees, lists, tables).
 * Supports custom sorting, filtering, and rendering.
 * <p>
 * Any number of viewer filters can be added to this viewer (using <code>addFilter</code>). 
 * When the viewer receives an update, it asks each of its filters if it is out of date,
 * and refilters elements as required.
 * </p>
 * @see ViewerFilter
 * @see ViewerSorter
 */
public abstract class StructuredViewer extends ContentViewer {