Bug 213040 [Markers] Selected filters not being kept on restart
When I select "Warnings on Selection" and then restart it is not selected when I come back in. We need to retain these selections. Note this is only a problem when selecting from the menu - from the dialog works fine.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/provisional/views/markers/MarkerContentGenerator.java
if (area != null)
				result.add(area);
		}
		return result;
	}
	/**
	 * Add all of the markers that pass the filters to results.
	 * 
	 * @param results
	 *            Collection of {@link IMarker}
	 * @param group
	 * @param markers
	 */
	private void filterMarkers(Collection results,
			MarkerFieldFilterGroup group, IMarker[] markers) {
		for (int idx = 0; idx < markers.length; idx++) {
			IMarker marker = markers[idx];
			if (group == null || group.select(marker))
				results.add(marker);
		}
	}
	/**
	 * Iterate through the return markers. If they do not exist in matching
	 * remove them.
	 * 
	 * @param matching
	 * @param returnMarkers
	 */
	private void findIntersection(Collection matching, Collection returnMarkers) {
		HashSet removeMarkers = new HashSet();