fixup! Don't forget to pass through filter to search

src/main/java/info/textgrid/services/aggregator/SearchResultList.java

@@ -147,7 +147,7 @@ protected void fetchNextChunk() {
 				Math.min(stop - nextStart, chunkSize), filter);
 		hits = Integer.parseInt(response.getHits());
 		logger.info(MessageFormat.format("Next query for {0}, filters {3}, sandbox {1}, {2} hits", query, searchClient.getSandbox(), hits,
-				Joiner.on("; ").join(filter)));
+				filter == null? "null" : Joiner.on("; ").join(filter)));
 		if (!started) {
 			availableResults = Lists.newArrayListWithExpectedSize(hits);
 			started = true;