Got this debugging another error. Filing here for reference. Original code: https://phabricator.intern.facebook.com/P59317705
/**
 * Copyright (c) 2013-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @flow
 */
import type {HostConfig, Deadline} from 'react-reconciler';
import type {Fiber} from './ReactFiber';
import type {FiberRoot, Batch} from './ReactFiberRoot';
import type {HydrationContext} from './ReactFiberHydrationContext';
import type {ExpirationTime} from './ReactFiberExpirationTime';
import ReactErrorUtils from 'shared/ReactErrorUtils';
import {ReactCurrentOwner} from 'shared/ReactGlobalSharedState';
import ReactStrictModeWarnings from './ReactStrictModeWarnings';
import {
  NoEffect,
  PerformedWork,
  Placement,
  Update,
  Snapshot,
  PlacementAndUpdate,
  Deletion,
  ContentReset,