Inline webworker issue since 2.3.4

[tjk]

Describe the bug

As of vite 2.3.4 (maybe due to #3468), inline webworkers generate Uncaught SyntaxError: Unexpected token 'export'. This error was not produced in chrome in vite 2.3.3 (see repro link below)

Reproduction

https://github.com/tjk/vite-inline-webworker-issue

System Info

  System:
    OS: Linux 5.10 Ubuntu 20.04.2 LTS (Focal Fossa)
    CPU: (16) x64 11th Gen Intel(R) Core(TM) i9-11900KF @ 3.50GHz
    Memory: 9.61 GB / 12.38 GB
    Container: Yes
    Shell: 5.0.17 - /bin/bash
  Binaries:
    Node: 12.18.1 - ~/.asdf/installs/nodejs/12.18.1/bin/node
    Yarn: 1.22.5 - ~/.asdf/shims/yarn
    npm: 6.14.5 - ~/.asdf/installs/nodejs/12.18.1/bin/npm
  npmPackages:
    @vitejs/plugin-vue: ^1.2.3 => 1.2.3
    vite: 2.3.4 => 2.3.4

Used package manager: yarn

[tjk]

Relevant links:

• https://discord.com/channels/804011606160703521/814182556068085760/856051587273064489
• fix(build): bundle non-inlined workers with rollup #2494 (comment)

[bluwy]

I've tested the repro in Vite 2.8.6. The issue seems to be fixed now.