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
IExtension extension = extensions[i];
			processExtension(tracker, extension, groupingEntries,
					attributeMappings);
		}
		postProcessExtensions(groupingEntries, attributeMappings);
		tracker.registerHandler(this, ExtensionTracker
				.createExtensionPointFilter(point));
	}
	/**
	 * Process the extension and register the result with the tracker. Fill the
	 * map of groupingEntries and attribueMappings processed for post
	 * processing.
	 * 
	 * @param tracker
	 * @param extension
	 * @param groupingEntries
	 *            Mapping of group names to the markerGroupingEntries registered
	 *            for them
	 * @param attributeMappings
	 *            the markerAttributeGroupings found
	 * @see #postProcessExtensions(Map, Collection)
	 */
	private void processExtension(IExtensionTracker tracker,
			IExtension extension, Map groupingEntries,
			Collection attributeMappings) {
		IConfigurationElement[] elements = extension.getConfigurationElements();
		for (int j = 0; j < elements.length; j++) {
			IConfigurationElement element = elements[j];
			if (element.getName().equals(PROBLEM_FILTER)) {
				ProblemFilter filter = newFilter(element);