docs: public String receiveVideoFrom(String sender, String sdpOffer) throws IOException {
      JsonObject params = new JsonObject();
      params.addProperty(RECEIVEVIDEO_SENDER_PARAM, sender);
      params.addProperty(RECEIVEVIDEO_SDPOFFER_PARAM, sdpOffer);
      JsonElement result = client.sendRequest(RECEIVEVIDEO_METHOD, params);
      return JsonRoomUtils.getResponseProperty(result, RECEIVEVIDEO_SDPANSWER_PARAM, String.class);
    }