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(console.error.calls.length).toBe(1);
      expect(console.error.argsForCall[0][0]).toBe(
        'Warning: validateDOMNesting(...): <tr> cannot appear as a child of ' +
        '<div>. See div > tr.'
      );
    });
    it('warns on invalid nesting at root', () => {
      spyOn(console, 'error');
      var p = document.createElement('p');
      ReactDOM.render(<span><p /></span>, p);
      expect(console.error.calls.length).toBe(1);
      expect(console.error.argsForCall[0][0]).toBe(
        'Warning: validateDOMNesting(...): <p> cannot appear as a descendant ' +
        'of <p>. See p > ... > p.'
      );
    });
    it('warns nicely for table rows', () => {
      spyOn(console, 'error');
      var Row = React.createClass({
        render: function() {
          return <tr />;
        },
      });
      var Foo = React.createClass({
        render: function() {
          return <table><Row /> </table>;
        },
      });
      ReactTestUtils.renderIntoDocument(<Foo />);
      expect(console.error.calls.length).toBe(2);