`ReactServerRenderingTransaction` doesn’t have a `checkpoint()`, so any component with `handleError()` crashes during server rendering. I tested on 15, but pretty sure this is in master as well.

Fiddle: https://jsfiddle.net/un1nqs0w/

cc @jimfb 

constructor(props) {
        super(props);
        this.state = {errorMessage: null};
      }
      render() {
        if (this.state.errorMessage != null) {
          log.push('Box renderError');
          return <div>Error: {this.state.errorMessage}</div>;
        }
        log.push('Box render');
        var ref = function(x) {
          log.push('Inquisitive ref ' + x);
        };
        return (
          <div>
            <Inquisitive ref={ref} />
            <Angry />
          </div>
        );
      }
      unstable_handleError(e) {