getCompareConfiguration(),
"action.EnableAncestor.", ICompareUIConstants.PROP_ANCESTOR_VISIBLE); //$NON-NLS-1$
a.setChecked(fAncestorVisible);
fAncestorItem = new ActionContributionItem(a);
fAncestorItem.setVisible(false);
tbm.appendToGroup("modes", fAncestorItem); //$NON-NLS-1$
tbm.getControl().addDisposeListener(a);
createToolItems(tbm);
updateToolItems();