Support for @layer CSS-rule

[simpleman383]

Added support for @layer CSS-rule (CSS Layer Block)

Gotta fix this issue and similar ones since jsdom utilizes this package.

[changeset-bot]

🦋 Changeset detected

Latest commit: f9c312c

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
rrweb-cssom	Minor

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[hasezoey]

Looks good to me, some minor style suggestions (according to surrounding code).
Please note that i am not involved with this project and dont know the other code other than this PR, i also am not involved with css parsing in general.

[simpleman383]

Actually, seems like there was no code style policy at all even before I touched the code for the first time 😁

[simpleman383]

Fixing code styling problem would bring A LOT of changes among different files (even the files irrelevant to the issue). Maybe the repo needs some refactoring in general...

[smitev]

What is the status of this PR?
@YunFeng0817 can we merge it?

[tijmenvangurp]

Any plans to get @layer support in? I can see this pr is open for a while, anything blocking to get it merged?

[smitev]

@YunFeng0817 it's been some time without attention to this PR.
can we get your feedback on it?