Bug 127861 [DataBinding] Mark API provisional
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/databinding/viewers/UpdatableTreeContentProvider.java
private IReadableSet model;
        
        
        private boolean childrenAddedToViewer = false;
        public ValueTreeNode(Object key) {
            node = key;
        }
        
        public void childrenAddedToViewer() {
        	this.childrenAddedToViewer = true;
        }
        
        public void addParent(Object parent) {
        	if (this.parent == null) {
        		this.parent = parent;
        	}
        	parents.add(parent);
        }
        
        public void removeParent(Object parent) {
        	parents.remove(parent);
        	if (parent == this.parent) {
        		if (parents.isEmpty()) {
        			this.parent = null;
        		} else {
        			this.parent = parents.iterator().next();
        		}
        	}
        }