Bug 99921 Empty working set name remains in working set group
3.1 RC3. If an empty working set is present (see bug ) the working set filter group always restores this one if none was selected before. I approve this one for 3.1 RC3 since the bug affects all JDT views and the fix is trivial. Dirk?
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/workingsets/WorkingSetFilterActionGroup.java
public boolean isFiltered(Object parent, Object object) {
	    if (fWorkingSetFilter == null)
	        return false;
	    return !fWorkingSetFilter.select(null, parent, object);
	}
	
	/**
	 * Returns the working set which is used by the filter.
	 * 
	 * @return the working set
	 */
	public IWorkingSet getWorkingSet() {
		return fWorkingSet;
	}
		
	/**
	 * Sets this filter's working set.
	 * 
	 * @param workingSet the working set
	 * @param refreshViewer Indiactes if the viewer should be refreshed.
	 */
	public void setWorkingSet(IWorkingSet workingSet, boolean refreshViewer) {
		
		fClearWorkingSetAction.setEnabled(workingSet != null);
		fEditWorkingSetAction.setEnabled(workingSet != null);
		fWorkingSet= workingSet;
		fWorkingSetFilter.setWorkingSet(workingSet);
		if (refreshViewer) {
			fChangeListener.propertyChange(new PropertyChangeEvent(this, IWorkingSetManager.CHANGE_WORKING_SET_CONTENT_CHANGE, null, workingSet));
		}