Bug 129812 [Markers] Enabling problem categorization per default
Build 3.2M5 Recent progress on problem categorization should be made more proeminent by enabling categorization by default. Similar to search view doing hierarchical presentation by default nowadays.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/MarkerSupportRegistry.java
private static final String SEVERITY = "severity";
	private static final String MARKER_TYPE_REFERENCE = "markerTypeReference"; 
	private static final String MARKER_CATEGORY = "markerCategory";
	private static final String ATTRIBUTE_MAPPING = "markerAttributeMapping"; 
	private static final String MARKER_GROUPING = "markerGrouping"; 
	private static final String ATTRIBUTE = "attribute"; 
	private static final String VALUE = "value"; 
	private static final String LABEL = "label"; 
	private static final String MARKER_ATTRIBUTE_GROUPING = "markerAttributeGrouping";
	private static final String DEFAULT_GROUPING_ENTRY = "defaultGroupingEntry";
	private static final String MARKER_TYPE = "markerType";
	private static final String PRIORITY = "priority"; 
	private static final String MARKER_GROUPING_ENTRY = "markerGroupingEntry"; 
	private static MarkerSupportRegistry singleton;
	
	private static Object creationLock = new Object();
	/**
	 * Get the instance of the registry.
	 * 
	 * @return MarkerSupportRegistry
	 */
	public static MarkerSupportRegistry getInstance() {
		if (singleton == null) {
			synchronized (creationLock) {
				if (singleton == null) {
					
					singleton = new MarkerSupportRegistry();
				}
			}
		}