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/views/markers/internal/ProblemFilter.java
public ProblemFilter(String filterName) {
		super(filterName, new String[] { IMarker.PROBLEM });
		if ((PlatformUI.getPreferenceStore()
				.getBoolean(IWorkbenchPreferenceConstants.USE_WINDOW_WORKING_SET_BY_DEFAULT))) {
			IWorkbenchWindow window = PlatformUI.getWorkbench()
					.getActiveWorkbenchWindow();
			if (window != null) {
				IWorkbenchPage page = window.getActivePage();
				if (page != null) {
					setOnResource(MarkerFilter.ON_WORKING_SET);
					setWorkingSet(page.getAggregateWorkingSet());
				}
			}
		}
	}
	public boolean selectMarker(ConcreteMarker marker) {
		if (!(marker instanceof ProblemMarker)) {
			return false;
		}
		ProblemMarker problemMarker = (ProblemMarker) marker;
		return !isEnabled()
				|| (super.selectMarker(problemMarker)
						&& selectByDescription(problemMarker) && selectBySeverity(problemMarker));
	}
	private boolean selectByDescription(ConcreteMarker item) {
		if (description == null || description.equals("")) { 
			return true;
		}
		String markerDescription = item.getDescription();
		int index = markerDescription.indexOf(description);