When creating an Element with a ref from inside of a constructor an error is thrown in production mode, but not in dev mode.

Here is a minimal sample:
https://jsfiddle.net/84v837e9/35/

An error, "Only a ReactOwner can have refs", should happen in dev and production modes.

This is happening in React 15.4
) {
        warning(
          false,
          '%s has a method called shouldComponentUpdate(). ' +
            'shouldComponentUpdate should not be used when extending React.PureComponent. ' +
            'Please extend React.Component if shouldComponentUpdate is used.',
          this.getName() || 'A pure component',
        );
      }
      warning(
        !inst.defaultProps,
        'Setting defaultProps as an instance property on %s is not supported and will be ignored.' +
          ' Instead, define defaultProps as a static property on %s.',
        this.getName() || 'a component',
        this.getName() || 'a component',
      );
    }
    var initialState = inst.state;
    if (initialState === undefined) {
      inst.state = initialState = null;
    }
    invariant(
      typeof initialState === 'object' && !Array.isArray(initialState),
      '%s.state: must be set to an object or null',
      this.getName() || 'ReactCompositeComponent',
    );
    this._pendingStateQueue = null;
    this._pendingReplaceState = false;
    this._pendingForceUpdate = false;
    if (inst.componentWillMount) {