We used to throw if event listener is not a function in Stack:

```js
ReactDOM.render(
  <h1 onClick={{}}>Hello World!</h1>,
  document.getElementById('container')
);
```

<img width="565" alt="screen shot 2017-08-08 at 3 41 08 pm" src="https://user-images.githubusercontent.com/810438/29077502-2646412e-7c50-11e7-8c99-3b7f6c0a2589.png">

Fiber silently ignores this.

I think we should throw. This would let us add support for objects (e.g. for passive listener configuration) if we want to in a minor rather than a major.
expect(nodeValueSetter.mock.calls.length).toBe(1);
      ReactDOM.render(<div checked={false} />, container);
      expect(nodeValueSetter.mock.calls.length).toBe(2);
      ReactDOM.render(<div checked={true} />, container);
      expect(nodeValueSetter.mock.calls.length).toBe(3);
    });
    it('should ignore attribute whitelist for elements with the "is: attribute', () => {
      var container = document.createElement('div');
      ReactDOM.render(<button is="test" cowabunga="chevynova" />, container);
      expect(container.firstChild.hasAttribute('cowabunga')).toBe(true);
    });
    it('should not update when switching between null/undefined', () => {
      var container = document.createElement('div');
      var node = ReactDOM.render(<div />, container);
      var setter = jest.fn();
      node.setAttribute = setter;
      ReactDOM.render(<div dir={null} />, container);
      ReactDOM.render(<div dir={undefined} />, container);
      ReactDOM.render(<div />, container);
      expect(setter.mock.calls.length).toBe(0);
      ReactDOM.render(<div dir="ltr" />, container);
      expect(setter.mock.calls.length).toBe(1);
    });
    it('handles multiple child updates without interference', () => {
      
      
      
      var container = document.createElement('div');
      
      ReactDOM.render(