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)

callbackCount++;
          ReactUpdates.asap(function() {
            callbackCount++;
          });
          expect(callbackCount).toBe(1);
        }, component);
        expect(callbackCount).toBe(0);
      },
    });
    var component = ReactTestUtils.renderIntoDocument(<A />);
    component.forceUpdate();
    expect(callbackCount).toBe(2);
  });
  it('calls asap callbacks with queued updates', function() {
    var log = [];
    var A = React.createClass({
      getInitialState: () => ({updates: 0}),
      render: function() {
        log.push('render-' + this.state.updates);
        return <div />;
      },
      componentDidUpdate: function() {
        if (this.state.updates === 1) {
          ReactUpdates.asap(function() {
            this.setState({updates: 2}, function() {
              ReactUpdates.asap(function() {
                log.push('asap-1.2');
              });
              log.push('setState-cb');
            });