React 0.14.7: `<option value="">empty</option>` emits empty string on change
http://jsbin.com/pisita/10/edit?html,js,console,output
React 15.0.0-rc.1`<option value="">empty</option>` emits string with value "empty" on change
http://jsbin.com/bemaze/12/edit?html,js,console,output
This is because React 15.0.0-rc.1 cuts off `value=""` from option tag

expect(
      !node.hasAttribute('value') || node.getAttribute('value').length > 0
    ).toBe(true);
  });
  it('should control radio buttons', function() {
    var RadioGroup = React.createClass({
      render: function() {
        return (
          <div>
            <input
              ref="a"
              type="radio"
              name="fruit"
              checked={true}
              onChange={emptyFunction}
            />A
            <input
              ref="b"
              type="radio"
              name="fruit"
              onChange={emptyFunction}
            />B
            <form>
              <input
                ref="c"
                type="radio"