Vendored useSubscription is not ES5-compatible

[merrywhether]

Verify canary release

• I verified that the issue exists in Next.js canary release

Provide environment information

Operating System:
  Platform: darwin
  Arch: arm64
  Version: Darwin Kernel Version 21.3.0: Wed Jan  5 21:37:58 PST 2022; root:xnu-8019.80.24~20/RELEASE_ARM64_T6000
Binaries:
  Node: 16.14.0
  npm: 8.3.1
  Yarn: 1.22.17
  pnpm: N/A
Relevant packages:
  next: 12.1.4
  react: 17.0.2
  react-dom: 17.0.2

What browser are you using? (if relevant)

No response

How are you deploying your application? (if relevant)

No response

Describe the Bug

A version of useSubscription interned/vendored into Next (#35746) because of its new peer-dep declaration. This version contains an arrow function which is not ES5-compatible.

Expected Behavior

Next currently states that it is ES5 compatible, so it should not contain this arrow function. #33227

I've also created #35913 to try to prevent these situations in the future.

To Reproduce

1. Create a next app (e.g. npx create-next-app@latest)
2. Add a dynamic import (the code-path that contains internal useSubscription usage). For example, change pages/index.js to dynamically import the Image component:

import Head from 'next/head';
import styles from '../styles/Home.module.css';
import dynamic from 'next/dynamic';
const Image = dynamic(() => import('next/image'));

3. Run next build
4. Run npx es-check es5 '.next/static/**/*.js'

Get error:

error: ES-Check: there were 1 ES version matching errors.

info: 
          ES-Check Error:
          ----
          · erroring file: .next/static/chunks/pages/index-35bd0f2403564f83.js
          · error: SyntaxError: Unexpected token (1:8374)
          · see the printed err.stack below for context
          ----

          SyntaxError: Unexpected token (1:8374)

[github-actions]

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