message: Room padlock decorations only if cross-signing is enabled
  Put the padlock decorations behind the labs flag as without the
  context of the shields on the room icons they can be a bit misleading
  and make people think it means 'encrypted'.
diff: @@ -426,6 +426,11 @@ module.exports = createReactClass({
  );
  }
  + let privateIcon = null;
  + if (SettingsStore.isFeatureEnabled("feature_cross_signing")) {
  + privateIcon = <div className="mx_RoomTile_PrivateIcon" />;
  + }
  +
  return <React.Fragment>
  <AccessibleButton
  tabIndex="0"
  @@ -444,7 +449,7 @@ module.exports = createReactClass({
  { dmIndicator }
  </div>
  </div>
  - <div className="mx_RoomTile_PrivateIcon" />
  + { privateIcon }
  <div className="mx_RoomTile_nameContainer">
  <div className="mx_RoomTile_labelContainer">
  { label }
  