We purge it [here](https://github.com/facebook/react/blob/b11540ccb2321aeb7259fcf0b3a38aeeea35231d/src/isomorphic/ReactDebugTool.js#L88-L89) but this code doesn’t run because of the [early exit](https://github.com/facebook/react/blob/b11540ccb2321aeb7259fcf0b3a38aeeea35231d/src/isomorphic/ReactDebugTool.js#L53-L57).

Need to fix this and add a test case to make sure we don’t regress on it.

return null;
      }
      function Qux() {
        return null;
      }
      delete Qux.name;
      var element = <div><Foo /><Baz /><Qux /></div>;
      var tree = {
        displayName: 'div',
        children: [{
          displayName: 'Bar',
          children: [],
        }, {
          displayName: 'Baz',
          children: [],
        }, {
          displayName: 'Unknown',
          children: [],
        }],
      };
      assertTreeMatches([element, tree]);
    });
    it('reports a native tree correctly', () => {
      var element = (
        <div>
          <p>
            <span>