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

Bug.

**What is the current behavior?**

Creating an `<input type='submit'` with `value={undefined}` results in a button with no text. https://codesandbox.io/s/nn7p94y3rl

The same behaviour can be seen with `type='reset'`

I have a PR open with a proposed fix. https://github.com/facebook/react/pull/12780

**What is the expected behavior?**

The input should use the browser's default value for the input (Submit for en, etc.).

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

React 16.3.2. Chrome 66.0.3359.139. macOS 10.13.4. Works in React 15 (unsure of earlier versions)

const markup = ReactDOMServer.renderToString(element);
    const div = document.createElement('div');
    div.innerHTML = markup;
    expect(div.firstChild.getAttribute('value')).toBe('1');
    expect(div.firstChild.getAttribute('defaultValue')).toBe(null);
  });
  it('should render name attribute if it is supplied', () => {
    const node = ReactDOM.render(<input type="text" name="name" />, container);
    expect(node.name).toBe('name');
    expect(container.firstChild.getAttribute('name')).toBe('name');
  });
  it('should render name attribute if it is supplied for SSR', () => {
    const element = <input type="text" name="name" />;
    const markup = ReactDOMServer.renderToString(element);
    const div = document.createElement('div');
    div.innerHTML = markup;
    expect(div.firstChild.getAttribute('name')).toBe('name');
  });
  it('should not render name attribute if it is not supplied', () => {
    ReactDOM.render(<input type="text" />, container);
    expect(container.firstChild.getAttribute('name')).toBe(null);
  });
  it('should not render name attribute if it is not supplied for SSR', () => {
    const element = <input type="text" />;
    const markup = ReactDOMServer.renderToString(element);
    const div = document.createElement('div');
    div.innerHTML = markup;
    expect(div.firstChild.getAttribute('name')).toBe(null);
  });
  it('should display "foobar" for `defaultValue` of `objToString`', () => {