shouldComponentUpdate(nextProps) {
        return this.props.idx !== nextProps.idx;
      }
      render() {
        return <span prop={this.props.idx} />;
      }
    }
    function Foo(props) {
      return (
        <div>
          <span prop={props.tick} />
          <div hidden={true}>
            <Bar idx={props.idx} />
            <Bar idx={props.idx + 1} />
          </div>
        </div>
      );
    }
    ReactNoop.render(<Foo tick={0} idx={0} />);
    ReactNoop.flushDeferredPri(40 + 25);
    expect(ReactNoop.getChildren()).toEqual([
      div(
        span(0),
        div(),
      ),
    ]);
    ReactNoop.render(<Foo tick={1} idx={0} />);
    ReactNoop.flushDeferredPri(35 + 25);
    expect(ReactNoop.getChildren()).toEqual([