Bug 214648 [Markers] AttributeMarkerGroupings and GroupingEntries not being cleaned up on removal
We are still leaving the references to AttributeMarkerGroupings and GroupingEntries when we unload
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/MarkerSupportRegistry.java
*/
	private TableComparator findSorterInChildren(String typeName,
			MarkerType type) {
		MarkerType[] types = type.getAllSubTypes();
		TableComparator defaultSorter = null;
		if (hierarchyOrders.containsKey(type.getId())) {
			defaultSorter = (TableComparator) hierarchyOrders.get(type.getId());
		}
		for (int i = 0; i < types.length; i++) {
			MarkerType[] subtypes = types[i].getAllSubTypes();
			for (int j = 0; j < subtypes.length; j++) {
				TableComparator sorter = findSorterInChildren(typeName,
						subtypes[j]);
				if (sorter != null) {
					return sorter;
				}
			}
		}
		return defaultSorter;
	}
	/**
	 * Return the FieldMarkerGroups in the receiver.
	 * 
	 * @return Collection of {@link MarkerGroup}
	 */
	public Collection getMarkerGroups() {
		return markerGroups.values();
	}
	/**
	 * Return the default groupfield.