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];
```

* here.
 */
var topLevelRootCounter = 1;
var TopLevelWrapper = function() {
  this.rootID = topLevelRootCounter++;
};
TopLevelWrapper.prototype.isReactComponent = {};
if (__DEV__) {
  TopLevelWrapper.displayName = 'TopLevelWrapper';
}
TopLevelWrapper.prototype.render = function() {
  
  return this.props;
};
/**
 * Mounting is the process of initializing a React component by creating its
 * representative DOM elements and inserting them into a supplied `container`.
 * Any prior content inside `container` is destroyed in the process.
 *
 *   ReactMount.render(
 *     component,
 *     document.getElementById('container')
 *   );
 *
 *   <div id="container">                   <-- Supplied `container`.
 *     <div data-reactid=".3">              <-- Rendered reactRoot of React
 *       // ...                                 component.
 *     </div>
 *   </div>
 *