message: Don't crash immediately if the room directory chunk is null/empty
  Fixes
diff: @@ -155,7 +155,7 @@ export default createReactClass({
  this.nextBatch = data.next_batch;
  this.setState((s) => {
  - s.publicRooms.push(...data.chunk);
  + s.publicRooms.push(...(data.chunk || []));
  s.loading = false;
  return s;
  });
  