Fix clearing of guests

[nickvergessen]

☑️ Resolves

• Fix "participants->update" is sent again and again once a guest left a conversation #9489

🏁 Checklist

• ⛑️ Tests (unit and/or integration) are included or not required
• 📘 API documentation in docs/ has been updated or is not required
• 📗 User documentation in https://github.com/nextcloud/documentation/tree/master/user_manual/talk has been updated or is not required
• 🔖 Capability is added or not needed

[danxuliu]

The cleaning of guests is triggered if the guests have default permissions or custom permissions, but all removed. However, the guests are not cleaned if they do not have default permissions, including custom permissions but all removed.

Other than that, tested and works 👍

[danxuliu]

Tested and works 👍

Out of curiosity, if all the permissions are removed for a guest, why is that guest cleared while guests with any other custom permissions are kept?

[nickvergessen]

Out of curiosity, if all the permissions are removed for a guest, why is that guest cleared while guests with any other custom permissions are kept?

My idea/thoughts were the following:

• When a guest has a name, we want to keep them so in comments the name is rendered
• When a guest could later on rejoin with the more permissions, we want to keep them so permissions can be revoked before they later on rejoin
• When a guest has less permissions, they can clear their cookies/website data and end up being a new guest with the default permissions, so keeping them is not as useful