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];
```

if (__DEV__) {
    if (!isProfiling || currentFlushNesting === 0) {
      currentFlushStartTime = null;
      currentFlushMeasurements = null;
      return;
    }
    var previousStartTime = currentFlushStartTime;
    var previousMeasurements = currentFlushMeasurements || [];
    var previousOperations = ReactNativeOperationHistoryDevtool.getHistory();
    if (previousMeasurements.length || previousOperations.length) {
      var registeredIDs = ReactComponentTreeDevtool.getRegisteredIDs();
      flushHistory.push({
        duration: performanceNow() - previousStartTime,
        measurements: previousMeasurements || [],
        operations: previousOperations || [],
        treeSnapshot: registeredIDs.reduce((tree, id) => {
          var ownerID = ReactComponentTreeDevtool.getOwnerID(id);
          var parentID = ReactComponentTreeDevtool.getParentID(id);
          tree[id] = {
            displayName: ReactComponentTreeDevtool.getDisplayName(id),
            text: ReactComponentTreeDevtool.getText(id),
            updateCount: ReactComponentTreeDevtool.getUpdateCount(id),
            childIDs: ReactComponentTreeDevtool.getChildIDs(id),
            
            ownerID: ownerID || ReactComponentTreeDevtool.getOwnerID(parentID),
            parentID,
          };
          return tree;
        }, {}),
      });