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.

displayName: 'Foo',
            children: [{
              displayName: 'Qux',
              children: [],
            }],
          }, {
            displayName: 'Bar',
            children: [{
              displayName: 'View',
              children: [{
                displayName: 'Text',
                children: [{
                  displayName: 'RCText',
                  children: [{
                    displayName: '#text',
                    text: 'Hi,',
                  }],
                }],
              }],
            }],
          }, {
            displayName: 'Image',
            children: [],
          }],
        }],
      };
      assertTreeMatches([element, tree]);
    });
    it('ignores null children', () => {
      class Foo extends React.Component {