Bug 81877 Package explorer forgets active working set [package explorer]
3.1 M4 1. open pkg explorer. 2. select a working set, pkg explorer updates and filters out projects. 3. close pkg explorer. 4. open package explorer again and the working set is no longer applied. This used to work.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
if (showProjects()) 
			return new PackageExplorerLabelProvider(AppearanceAwareLabelProvider.DEFAULT_TEXTFLAGS | JavaElementLabels.P_COMPRESSED,
				AppearanceAwareLabelProvider.DEFAULT_IMAGEFLAGS | JavaElementImageProvider.SMALL_ICONS,
				fContentProvider);
		else
			return new WorkingSetAwareLabelProvider(AppearanceAwareLabelProvider.DEFAULT_TEXTFLAGS | JavaElementLabels.P_COMPRESSED,
				AppearanceAwareLabelProvider.DEFAULT_IMAGEFLAGS | JavaElementImageProvider.SMALL_ICONS,
				fContentProvider);			
	}
	
	private IElementComparer createElementComparer() {
		if (showProjects()) 
			return null;
		else
			return WorkingSetModel.COMPARER;
	}
	
	private void fillActionBars() {
		IActionBars actionBars= getViewSite().getActionBars();
		fActionSet.fillActionBars(actionBars);
	}
	
	private Object findInputElement() {
		if (showWorkingSets()) {
			return fWorkingSetModel;
		} else {
			Object input= getSite().getPage().getInput();
			if (input instanceof IWorkspace) { 
				return JavaCore.create(((IWorkspace)input).getRoot());
			} else if (input instanceof IContainer) {