Bug 184755 [DataBinding] internal tree content provider does not work
I broke the tree content providers while trying to update them to use TreePaths. It would be good to have a working implementation again...
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/internal/databinding/internal/viewers/UnorderedTreeContentProvider.java
UnorderedTreeNode result = (UnorderedTreeNode) mapElementToTreeNode
				.get(element);
		if (result != null && result.getParent() == null) {
			mapElementToTreeNode.remove(element);
			elements.doFireDiff(Collections.EMPTY_SET, Collections
					.singleton(element));
			result.dispose();
		}
	}
	private void setViewer(Viewer viewer) {
		if (!(viewer instanceof TreeViewer)) {
			throw new IllegalArgumentException(
					"This content provider can only be used with TreeViewers"); 
		}
		TreeViewer newTreeViewer = (TreeViewer) viewer;
		if (newTreeViewer != treeViewer) {
			if (treeViewer != null) {
				treeViewer.removeTreeListener(expandListener);
			}
			this.treeViewer = newTreeViewer;
			if (newTreeViewer != null) {
				newTreeViewer.addTreeListener(expandListener);
			}
		}
	}
	public Object[] getChildren(TreePath parentPath) {
		Set result = getNode(parentPath).getChildren();
		addParent(parentPath, result);
		return result.toArray();
	}