**Do you want to request a *feature* or report a *bug*?**

bug? Maybe.

**What is the current behavior?**

Using non-delegated handler for submit event.

**What is the expected behavior?**

After IE9, at least I know, submit event bubbled up.

**Which versions of React, and which browser / OS are affected by this issue? Did this work in previous versions of React?**

16.2.0
getInner = () => {
        return this.refs.inner;
      };
      render() {
        const inner = <div ref="inner">Inner</div>;
        return (
          <div>
            <div onMouseOut={onMouseOut} id="outer">
              {inner}
            </div>
          </div>
        );
      }
    }
    const container = document.createElement('div');
    const instance = ReactDOM.render(<Wrapper />, container);
    document.body.appendChild(container);
    const nativeEvent = document.createEvent('Event');
    nativeEvent.initEvent('mouseout', true, true);
    instance.getInner().dispatchEvent(nativeEvent);
    expect(mouseOut).toBeCalled();
    expect(mouseOut).toHaveBeenCalledTimes(1);
    expect(mouseOut.mock.calls[0][0]).toEqual(instance.getInner());