I've observed that when React's profiling mode is enabled, updating the profiling fields [here](https://github.com/facebook/react/blob/1d25aa5787d4e19704c049c3cfa985d3b5190e0d/packages/react-reconciler/src/ReactProfilerTimer.js#L46) and [here](https://github.com/facebook/react/blob/1d25aa5787d4e19704c049c3cfa985d3b5190e0d/packages/react-reconciler/src/ReactProfilerTimer.js#L69-L71) during the _render_ phase seems to cause a significant deopt in [`getHostSibling`](https://github.com/facebook/react/blob/1d25aa5787d4e19704c049c3cfa985d3b5190e0d/packages/react-reconciler/src/ReactFiberCommitWork.js#L858-L898) during the _commit_ phase for Chrome only. (Neither Safari nor Firefox seem to be affected by this.)

I have created a repro case with inline annotations here:
https://github.com/bvaughn/react-profiling-v8-deopt-repro#about-this-repro-case

(Note that the above repo is private. Please tag me here if you need access.)
/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * 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 {ReactElement, Source} from 'shared/ReactElementType';
import type {ReactFragment, ReactPortal, RefObject} from 'shared/ReactTypes';
import type {WorkTag} from 'shared/ReactWorkTags';
import type {TypeOfMode} from './ReactTypeOfMode';
import type {SideEffectTag} from 'shared/ReactSideEffectTags';
import type {ExpirationTime} from './ReactFiberExpirationTime';
import type {UpdateQueue} from './ReactUpdateQueue';
import type {ContextDependency} from './ReactFiberNewContext';
import invariant from 'shared/invariant';
import warningWithoutStack from 'shared/warningWithoutStack';
import {enableProfilerTimer} from 'shared/ReactFeatureFlags';
import {NoEffect} from 'shared/ReactSideEffectTags';
import {
  IndeterminateComponent,
  ClassComponent,
  HostRoot,
  HostComponent,
  HostText,
  HostPortal,