**Do you want to request a _feature_ or report a _bug_?**

This is a bug

**What is the current behavior?**

![screen shot 2016-07-03 at 4 12 19 pm](https://cloud.githubusercontent.com/assets/1697380/16544656/b3f896b2-4140-11e6-923a-06fc630c92df.png)
![screen shot 2016-07-03 at 4 11 15 pm](https://cloud.githubusercontent.com/assets/1697380/16544657/b3f8f292-4140-11e6-8b03-0ecaa3165460.png)

**If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem via https://jsfiddle.net or similar (template: https://jsfiddle.net/reactjs/69z2wepo/).**

Using 15.2.0 react and react-dom

**What is the expected behavior?**

![screen shot 2016-07-03 at 4 13 05 pm](https://cloud.githubusercontent.com/assets/1697380/16544659/b938951e-4140-11e6-9275-2c3721542003.png)
![screen shot 2016-07-03 at 4 13 10 pm](https://cloud.githubusercontent.com/assets/1697380/16544660/b9391278-4140-11e6-9951-0f81024ce859.png)

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

In 15.2.0, extra attributes `name` and `value` with empty values are added to the submit button of a form.

It works in 15.1.0.

ReactDOM.render(
        <input
          type="radio"
          checked={true}
          defaultChecked={true}
          readOnly={true}
        />,
        container,
      ),
    ).toWarnDev(
      'A component contains an input of type radio with both checked and defaultChecked props. ' +
        'Input elements must be either controlled or uncontrolled ' +
        '(specify either the checked prop, or the defaultChecked prop, but not ' +
        'both). Decide between using a controlled or uncontrolled input ' +
        'element and remove one of these props. More info: ' +
        'https://fb.me/react-controlled-components',
    );
    ReactDOM.unmountComponentAtNode(container);
    ReactDOM.render(
      <input
        type="radio"
        checked={true}
        defaultChecked={true}
        readOnly={true}
      />,
      container,
    );
  });
  it('should warn if value and defaultValue props are specified', () => {
    expect(() =>