Bug 64890 Package explorer out of sync when open/closing projects [package explorer]
RC1 - close a project - Open the closed project in a new window va Open in New Window context menu action - open the project observe: the Java project is rendered in the additional window as folders and CUs not on the class path.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerActionGroup.java
*     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.internal.ui.packageview;
import org.eclipse.core.resources.IContainer;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.jface.action.IAction;
import org.eclipse.jface.action.IMenuManager;
import org.eclipse.jface.action.IToolBarManager;
import org.eclipse.jface.action.Separator;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.OpenStrategy;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.jface.viewers.DoubleClickEvent;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.OpenEvent;
import org.eclipse.jface.viewers.SelectionChangedEvent;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.ui.IActionBars;
import org.eclipse.ui.IMemento;
import org.eclipse.ui.IWorkbenchActionConstants;
import org.eclipse.ui.IWorkbenchPartSite;
import org.eclipse.ui.IWorkingSet;
import org.eclipse.ui.IWorkingSetManager;
import org.eclipse.ui.actions.ActionFactory;
import org.eclipse.ui.actions.ActionGroup;
import org.eclipse.ui.actions.OpenInNewWindowAction;
import org.eclipse.ui.views.framelist.BackAction;
import org.eclipse.ui.views.framelist.ForwardAction;