Bug 130976 [Viewers] Error is calculation of parent path when calling TreePathViewerSorter
There is an error in the parent path calculation in AbstractTreeViewer#getSortedChildren. If the input of the viewer is passed, a tee path of length one is passed to the sorter but a null should be passed (as mentioned in the method spec). I will attach a patch.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
if (usingElementMap()) {
			disassociateChildren(item);
		}
    }
    /**
     * Disassociates the children of the given SWT item from their
     * corresponding elements.
     * 
     * @param item
     *           the widget
     */
    private void disassociateChildren(Item item) {
        Item[] items = getChildren(item);
        for (int i = 0; i < items.length; i++) {
            if (items[i].getData() != null) {
				disassociate(items[i]);
			}
        }
    }
    
    protected Widget doFindInputItem(Object element) {
        
        Object root = getRoot();
        if (root == null) {
			return null;
		}
        if (equals(root, element)) {