Bug 93360 [Viewers] getChild still used in indexForElement
indexForElement() in AbstractTreeViewer still uses getChild() and not getChildren(). This should probably also change to using getChildren() and do the same thing as insertionPosition().
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
refresh(element);
					break;
				}
			}
			createTreeItem(widget, element, index);		
		}
    }
	
	/**
     * 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.
     * @return the index to use when inserting the element.
     * 
     */
	
	private int insertionPosition(Item[] items,  ViewerSorter sorter, int lastInsertion, Object element) {
	    
		int size = items.length;
		if (sorter == null)