Bug 167450 [DataBinding] Get rid of bind support factory magic
I finally realized that we don't need that other magic factory. I'll move fillBindSpecDefaults() and the methods it calls (createConverter, createValidator etc) to a new class DefaultBindSpec. Clients who want default validators and converters created for them just create a DefaultBindSpec as opposed to a (rather empty) BindSpec. I will also move the early type checking into DefaultBindSpec to make it optional as well.
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/databinding/viewers/UnorderedTreeNode.java
*  
     * @return
     */
    public Set getChildren() {
        if (!listeningToChildren) {
            listeningToChildren = true;
            children.addSetChangeListener(this);
            hasPendingNode = children.isEmpty() && children.isStale();
            children.addStaleListener(this);
            updateStale();
        }
        
        
        if (hasPendingNode) {
            Object pendingNode = contentProvider.getPendingNode();
            return Collections.singleton(pendingNode);
        }
        return children;
    }
    
    /**
     * @return
     */
    public IObservableSet getChildrenSet() {
        return children;
    }
    
    private void updateStale() {
        boolean willBeStale = children.isStale();
        if (willBeStale != isStale) {