Got this debugging another error. Filing here for reference. Original code: https://phabricator.intern.facebook.com/P59317705
scheduleWork,
    computeExpirationForFiber,
    markLegacyErrorBoundaryAsFailed,
    recalculateCurrentTime,
  );
  const {
    now,
    scheduleDeferredCallback,
    cancelDeferredCallback,
    prepareForCommit,
    resetAfterCommit,
  } = config;
  
  const originalStartTimeMs = now();
  let mostRecentCurrentTime: ExpirationTime = msToExpirationTime(0);
  let mostRecentCurrentTimeMs: number = originalStartTimeMs;
  
  let lastUniqueAsyncExpiration: number = 0;
  
  
  
  let expirationContext: ExpirationTime = NoWork;
  let isWorking: boolean = false;
  
  let nextUnitOfWork: Fiber | null = null;
  let nextRoot: FiberRoot | null = null;
  
  let nextRenderExpirationTime: ExpirationTime = NoWork;
  
  let nextEffect: Fiber | null = null;