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];
```

return node.getAttribute && node.getAttribute(ATTR_NAME) || '';
}
/**
 * Mounts this component and inserts it into the DOM.
 *
 * @param {ReactComponent} componentInstance The instance to mount.
 * @param {DOMElement} container DOM element to mount into.
 * @param {ReactReconcileTransaction} transaction
 * @param {boolean} shouldReuseMarkup If true, do not insert markup
 */
function mountComponentIntoNode(
  wrapperInstance,
  container,
  transaction,
  shouldReuseMarkup,
  context
) {
  var markerName;
  if (ReactFeatureFlags.logTopLevelRenders) {
    var wrappedElement = wrapperInstance._currentElement.props;
    var type = wrappedElement.type;
    markerName = 'React mount: ' + (
      typeof type === 'string' ? type :
      type.displayName || type.name