Bug 141192 [Viewers] Javadoc change about multiple equal elements in StructuredViewer and AbstractTreeViewer
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
* @param element
     *           The element to insert.
     * @return int
     */
    protected int indexForElement(Widget parent, Object element) {
        ViewerComparator comparator = getComparator();
        TreePath parentPath = internalGetSorterParentPath(parent, comparator);
		
		Item[] items = getChildren(parent);
		int count = items.length;
        if (comparator == null) {
			return count;
		}
        int min = 0, max = count - 1;
        while (min <= max) {
            int mid = (min + max) / 2;
            Object data = items[mid].getData();
            int compare = internalCompare(comparator, parentPath, data, element);
            if (compare == 0) {
                
                while (compare == 0) {
                    ++mid;
                    if (mid >= count) {
                        break;
                    }
                    data = items[mid].getData();
                    compare = internalCompare(comparator, parentPath, data, element);
                }
                return mid;
            }