Hello,

After updating to React 15.0.1, we are getting the following error:

```
Uncaught TypeError: Cannot read property 'addEventListener' of null
```

![image](https://cloud.githubusercontent.com/assets/4996164/14602577/5bb4e9f2-0571-11e6-9aa1-98de49f50d76.png)

},
      render: function() {
        return <div>{this.state.x}</div>;
      },
    });
    var instance = ReactTestUtils.renderIntoDocument(<Component />);
    expect(instance.state.x).toBe(0);
    var innerCallbackRun = false;
    ReactUpdates.batchedUpdates(function() {
      instance.setState({x: 1}, function() {
        instance.setState({x: 2}, function() {
          expect(this).toBe(instance);
          innerCallbackRun = true;
          expect(instance.state.x).toBe(2);
          expect(updateCount).toBe(2);
        });
        expect(instance.state.x).toBe(1);
        expect(updateCount).toBe(1);
      });
      expect(instance.state.x).toBe(0);
      expect(updateCount).toBe(0);
    });
    expect(innerCallbackRun).toBeTruthy();
    expect(instance.state.x).toBe(2);
    expect(updateCount).toBe(2);
  });
  it('should batch forceUpdate together', function() {
    var shouldUpdateCount = 0;
    var updateCount = 0;
    var Component = React.createClass({