private void collectUniversityChanges(CourseModel courseModel,
			ArrayList<Change> changes) {
		// TODO: is there some API to get university descriptions? They do have
		// numeric codes in facets.
		for (String u : universities) {
			String code = makeIdSafe(u);
			if (courseModel.getUniversity(Source.EDX, code) == null)
				changes.add(DescChange.add(DescChange.UNIVERSITY, Source.EDX,
						code, u, null));
		}
		HashSet<String> newIds = new HashSet<String>();
		for (String s : this.universities)
			newIds.add(makeIdSafe(s));
		for (DescRec rec : courseModel.getUniversities(Source.EDX)) {
			if (!newIds.contains(rec.getId())) {
				changes.add(DescChange.delete(DescChange.UNIVERSITY, rec));
			} else {
				// TODO Once we get description for universities, diff them.
			}
			newIds.remove(rec.getId());
		}
	}