I was testing latest refactor of PerfTools.
When using printOperations() often (but not always) I get 

```
Uncaught TypeError: Cannot read property 'displayName' of undefined
```

in getOperations() on the line:

```
var {displayName, ownerID} = treeSnapshot[instanceID];
```

ReactDOM.render(<div style={{
        color: 'blue',
        backgroundColor: 'yellow',
      }} />, node);
      ReactDOM.render(<div style={{ backgroundColor: 'green' }} />, node);
      ReactDOM.render(<div />, node);
      assertHistoryMatches([{
        instanceID: inst._debugID,
        type: 'update styles',
        payload: { color: 'red' },
      }, {
        instanceID: inst._debugID,
        type: 'update styles',
        payload: { color: 'blue', backgroundColor: 'yellow' },
      }, {
        instanceID: inst._debugID,
        type: 'update styles',
        payload: { color: '', backgroundColor: 'green' },
      }, {
        instanceID: inst._debugID,
        type: 'update styles',
        payload: { backgroundColor: '' },
      }]);
    });
    it('gets ignored if the styles are shallowly equal', () => {
      var node = document.createElement('div');
      ReactDOM.render(<div />, node);
      var inst = ReactDOMComponentTree.getInstanceFromNode(node.firstChild);
      ReactNativeOperationHistoryDevtool.clearHistory();
      ReactDOM.render(<div style={{