Runtime error in production build of DLL which contains package with "sideEffects": false and not used module

[mifopen]

Bug report

What is the current behavior?
Uncaught TypeError: Cannot read property 'call' of undefined

If the current behavior is a bug, please provide the steps to reproduce.
Minimal reproduction: https://github.com/mifopen/webpack-bug-example
@sentry/browser is used as an example of package with "sideEffects": false
Steps to reproduce:

1. Clone the repo
2. Run yarn/npm run build-vendor
3. Run yarn/npm run build-app
4. Open index.html file in browser
5. Open console to see error

Why?
Module LogLevel from @sentry/types (dep of @sentry/browser) is exported from the package but isn't used. webpack excludes it from DLL because of production mode and "sideEffects": false, but DllPlugin somehow requires it anyway.

What is the expected behavior?
Generate DLL without unused modules at all

Other relevant information:
webpack version: 4.31.0
Node.js version: 11.1
Operating System: macos 10.14.4

[sokra]

Yep this is a bug.