*feature*

>Warning: A component is `contentEditable` and contains `children` managed by React. It is now your responsibility to guarantee that none of those nodes are unexpectedly modified or duplicated. This is probably not intentional.

It would help heaps if I would know _which_ component is causing this.
render() {
          return <tr>x</tr>;
        }
      }
      class Foo extends React.Component {
        render() {
          return <table><Row /> </table>;
        }
      }
      ReactTestUtils.renderIntoDocument(<Foo />);
      expectDev(console.error.calls.count()).toBe(3);
      expectDev(normalizeCodeLocInfo(console.error.calls.argsFor(0)[0])).toBe(
        'Warning: validateDOMNesting(...): <tr> cannot appear as a child of ' +
          '<table>. Add a <tbody> to your code to match the DOM tree generated ' +
          'by the browser.' +