Updating css-tree lib & creating media-query-calc test - #5876

[Victomas97]

Before submitting the PR, please make sure you do the following

• It's really useful if your PR references an issue where it is discussed ahead of time. In many cases, features are absent for a reason. For large changes, please create an RFC: https://github.com/sveltejs/rfcs
• This message body should clearly illustrate what problems it solves.
• Ideally, include a test that fails without this PR but passes with it.

Tests

• Run the tests with npm test and lint the project with npm run lint

THIS ISSUE IS NOT FINISHED BEACUSE I HAVE SOME QUESTIONS.

Hi! I'm new here. I created a test to try media-query-calc and i tryied to update css-tree because this current version don't support media queries calc... But I have some problems on compiles.js and obviusly i can't commit it.
SOME HELP!?

[ludofischer]

Did you run the existing tests? When I updated css-tree, many tests failed. If I remember correctly I got a lot of 'maximum stack depth' errors. Is that also what you are seeing?

[benmccann]

Closing in favor of #5958