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)

var publicInstance = this._instance;
  if (this._debugID !== 0) {
    ReactInstrumentation.debugTool.onBeginLifeCycleTimer(
      this._debugID,
      'componentDidUpdate'
    );
  }
  publicInstance.componentDidUpdate(prevProps, prevState, prevContext);
  if (this._debugID !== 0) {
    ReactInstrumentation.debugTool.onEndLifeCycleTimer(
      this._debugID,
      'componentDidUpdate'
    );
  }
}
function shouldConstruct(Component) {
  return Component.prototype && Component.prototype.isReactComponent;
}
/**
 * ------------------ The Life-Cycle of a Composite Component ------------------
 *
 * - constructor: Initialization of state. The instance is now retained.
 *   - componentWillMount
 *   - render
 *   - [children's constructors]
 *     - [children's componentWillMount and render]
 *     - [children's componentDidMount]
 *     - componentDidMount
 *
 *       Update Phases: