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
}
	/*
	 * @see org.eclipse.ui.views.navigator.IResourceNavigator#setLinkingEnabled(boolean)
	 * @since 2.1
	 */
	public void setLinkingEnabled(boolean enabled) {
		fLinkingEnabled= enabled;
		PreferenceConstants.getPreferenceStore().setValue(PreferenceConstants.LINK_PACKAGES_TO_EDITOR, enabled);
		if (enabled) {
			IEditorPart editor = getSite().getPage().getActiveEditor();
			if (editor != null) {
				editorActivated(editor);
			}
		}
	}
	/**
	 * Returns the name for the given element.
	 * Used as the name for the current frame. 
	 */
	String getFrameName(Object element) {
		if (element instanceof IJavaElement) {
			return ((IJavaElement) element).getElementName();
		} else if (element instanceof WorkingSetModel) {
			return ""; 
		} else {
			return fLabelProvider.getText(element);
		}
	}
	
	void projectStateChanged(Object root) {