Bug 221521 [Markers] New markers API needs to be pared down
We have too much API in some of the new classes and they can be moved to internals
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/MarkerComparator.java
private MarkerField[] fields;
	/**
	 * Constant to indicate an ascending sort direction.
	 */
	public static final int ASCENDING = 1;
	/**
	 * Constant to indicate an descending sort direction.
	 */
	public static final int DESCENDING = -1;
	private static final String PRIMARY_SORT_FIELD_TAG = "PRIMARY_SORT_FIELD"; 
	private static final String DESCENDING_FIELDS = "DESCENDING_FIELDS"; 
	
	HashSet descendingFields = new HashSet();
	/**
	 * Create a new instance of the receiver categorised by categoryField
	 * 
	 * @param categoryField
	 *            May be <code>null/<code>
	 * @param mainFields in order of compare significance
	 */
	public MarkerComparator(MarkerField categoryField, MarkerField[] mainFields) {
		category = categoryField;
		fields = mainFields;
	}
	/**
	 * Compare the two objects to see if they have the same category value
	 * 
	 * @param object1