Bug 154064 Need a way to access the TreeItem or TableItem on a refresh
It is not currently possible to know when an item is refreshed. This is required for ownerDraw support in viewers.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/ColumnViewer.java
*/
	public abstract Object[] getColumnProperties();
	/**
	 * Return the TableColumnViewer at columnIndex
	 * 
	 * @param columnIndex
	 * @return TableColumnViewer
	 */
	public ViewerColumn getColumnViewer(final int columnIndex) {
		ViewerColumn viewer;
		Widget columnOwner = getColumnViewerOwner(columnIndex);
		if (columnOwner == null) {
			return null;
		}
		viewer = (ViewerColumn) columnOwner
				.getData(ViewerColumn.COLUMN_VIEWER_KEY);
		if (viewer == null) {
			viewer = createColumnViewer(columnOwner, ViewerLabelProvider
					.createViewerLabelProvider(getLabelProvider()));
			if (getCellModifier() != null) {
				viewer.setEditingSupport(new EditingSupport() {
					/*
					 * (non-Javadoc)
					 * 
					 * @see org.eclipse.jface.viewers.EditingSupport#canEdit(java.lang.Object)
					 */
					public boolean canEdit(Object element) {
						return getCellModifier().canModify(element,
								(String) getColumnProperties()[columnIndex]);
					}