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
*/
    public Object getParent() {
        return parent;
    }
    
    /**
     * @return
     */
    public Set getParents() {
        if (parents == null) {
            if (parent == null) {
                return Collections.EMPTY_SET;
            } else {
                return Collections.singleton(parent);
            }
        } else {
            return parents;
        }
    }
    
    /**
     * Called when the child set changes. Should not be called directly by the viewer.
     */
    public void handleSetChange(IObservableSet source, SetDiff diff) {
        boolean shouldHavePendingNode = children.isEmpty() && children.isStale();
        
        Set additions = diff.getAdditions();
        
        if (shouldHavePendingNode && !hasPendingNode) {
            HashSet newAdditions = new HashSet();