See the original report in https://github.com/facebook/react/issues/10772#issuecomment-333242375.

The problem is that SVG is case sensitive, and so naïvely setting `tabIndex` and relying on insensitivity won't work with it.

The good news is it seems like `tabindex` is the only valid [SVG attribute](https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute) with this problem. We just missed it because it applies both to HTML and SVG.

I think the fix is to add it back to the whitelist. 
render() {
          
          return <div id="classWrongChild">{this.context.text}</div>;
        }
      }
      ClassChildWithWrongContext.contextTypes = {foo: PropTypes.string};
      const e = await render(
        <PurpleContext><ClassChildWithWrongContext /></PurpleContext>,
      );
      expect(e.textContent).toBe('');
    });
    itRenders('stateless child with wrong context', async render => {
      function StatelessChildWithWrongContext(props, context) {
        
        return <div id="statelessWrongChild">{context.text}</div>;
      }
      StatelessChildWithWrongContext.contextTypes = {
        foo: PropTypes.string,
      };
      const e = await render(
        <PurpleContext><StatelessChildWithWrongContext /></PurpleContext>,
      );
      expect(e.textContent).toBe('');
    });
    itRenders('with context passed through to a grandchild', async render => {
      function Grandchild(props, context) {