Bug 127861 [DataBinding] Mark API provisional
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/databinding/viewers/UpdatableSetContentProvider.java
void doFireStale(boolean isStale) {
        	fireStale(isStale);
        }
    }
    /**
     * This readableSet returns the same elements as the input readableSet. However, it only fires
     * events AFTER the elements have been added or removed from the viewer.
     */
    private KnownElementsSet elements = new KnownElementsSet();
    
    private IChangeListener listener = new IChangeListener() {
        
    	public void handleChange(ChangeEvent changeEvent) {
    		if (isDisposed()) {
    			return;
    		}
    		
    		switch (changeEvent.getChangeType()) {
    		case ChangeEvent.ADD_MANY:
    			added((Collection)changeEvent.getNewValue());
    			break;
    		case ChangeEvent.REMOVE_MANY:
    			doRemove((Collection)changeEvent.getNewValue(), !viewer.getControl().isDisposed());
    			break;
    		case ChangeEvent.STALE:
    			elements.doFireStale(((Boolean)changeEvent.getNewValue()).booleanValue());
    			break;
    		}
    	}