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
/**
     * Returns the index where the item should be inserted. It uses sorter to
     * determine the correct position, if sorter is not assigned, returns the
     * index of the element after the last.
     * 
     * @param items the items to search
     * @param sorter The sorter to use.
     * @param lastInsertion
     *            the start index to start search for position from this allows
     *            optimising search for multiple elements that are sorted
     *            themself.
     * @param element
     *            element to find position for.
     * @param parentPath the tree path for the element's parent or <code>null</code>
     * if the element is a root element or the sorter is not a {@link TreePathViewerSorter}
     * @return the index to use when inserting the element.
     * 
     */
	
	private int insertionPosition(Item[] items,  ViewerSorter sorter, int lastInsertion, Object element, TreePath parentPath) {
		
		int size = items.length;
		if (sorter == null) {
			return size;
		}
	    int min = lastInsertion, max = size - 1;
		while (min <= max) {
            int mid = (min + max) / 2;
            Object data = items[mid].getData();
            int compare = internalCompare(sorter, parentPath, data, element);