Bug 91409 Project Open/Close items are disabled when Package Explorer active
Project Open/Close option in the Project menu is disabled in Plugin prespective.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerActionGroup.java
} else {
				IAction openAction= fNavigateActionGroup.getOpenAction();
				if (openAction != null && openAction.isEnabled() && OpenStrategy.getOpenMethod() == OpenStrategy.DOUBLE_CLICK)
					return;
				viewer.setExpandedState(element, !viewer.getExpandedState(element));
			}
		}
	}
	
	 void handleOpen(OpenEvent event) {
		IAction openAction= fNavigateActionGroup.getOpenAction();
		if (openAction != null && openAction.isEnabled()) {
			openAction.run();
			return;
		}
	}
	
	 void handleKeyEvent(KeyEvent event) {
		if (event.stateMask != 0) 
			return;		
		
		if (event.keyCode == SWT.BS) {
			if (fUpAction != null && fUpAction.isEnabled()) {
				fUpAction.run();
				event.doit= false;
			}
		}
	}
	
	private void doWorkingSetChanged(PropertyChangeEvent event) {