static _maybeInit() {
    if (!BugReporting._subscription) {
      BugReporting._subscription = RCTDeviceEventEmitter
          .addListener('collectBugExtraData', BugReporting.collectExtraData, null);
      defaultExtras();
    }

    if (!BugReporting._redboxSubscription) {
      BugReporting._redboxSubscription = RCTDeviceEventEmitter
          .addListener('collectRedBoxExtraData', BugReporting.collectExtraData, null);
    }
  }
A simple class for collecting bug report data. Components can add sources that will be queried when a bug report
is created via `collectExtraData`. For example, a list component might add a source that provides the list of rows
that are currently visible on screen. Components should also remember to call `remove()` on the object that is
returned by `addSource` when they are unmounted.