Bug 294303 [Markers] 'Queuing Viewer Updates' in Problems view
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/MarkerUpdateJob.java
IProgressMonitor.UNKNOWN);
			buildMarkers(monitor);
		} finally {
			building = false;
		}
		return Status.OK_STATUS;
	}
	/**
	 * gather all markers needed by the view.
	 * 
	 * @param monitor
	 */
	protected void buildMarkers(IProgressMonitor monitor) {
		MarkersChangeListener markersListener = builder.getMarkerListener();
		if (monitor.isCanceled()) {
			return;
		}
		
		markersListener
				.indicateStatus(
						MarkerMessages.MarkerView_searching_for_markers, false);
		if (clean || !isIncremental()) {
			clean = !clean(markersListener, monitor);
		}
		if (monitor.isCanceled()) {
			return;
		}
		List markers = markersListener.getMarkerEntryList();
		if (monitor.isCanceled()) {
			return;