Motivation / Problem

#9467 asked if we could remove the COMPANY_INFO packets, as they are now unused (by our clients).

Description

To get a bit of visual what it involves, I created this PR. I have several reservations whether this is a good idea or not.

• This also removes any other (custom) client to get company info. But to counter that, Suggestion: Option not to disclose server information when password-protected #7268 has a good point that showing company info on a private server is a bit weird .. and not really what you expect in 2021. So removing this would also work towards resolving Suggestion: Option not to disclose server information when password-protected #7268.
• COMPANY_INFO is part of the DO NOT CHANGE THIS .. which makes me wonder if there is anything I am overlooking, why this would be bad. I noticed I failed to estimate the impact of this.
• Currently you can gather this information from every server in the public listing. That might not have been the intention of this packet, but this removes that ability. It has to be noted that the admin port still has the ability to get the company info, but this of course requires authorization.
• Servers might use this on a banner to show who is on their server, how many trains, etc. They really should be using the admin port for that, but one cannot guarantee someone is using this.

We can also do everything "in between". Only remove the client-side, only remove the server-side, leave it alone.

I am rather conflicted about this, but I just present this PR so we can have a talk.

Edit: the more I think about it, the more I think all cases I mention where people might be using this packet, are illegal use of the packet. Additionally, #7268 really points out this packet should not exist in this form. So I do think we should remove it. Means we can also safely close #7268, as with this PR (combined with all the other work done on multiplayer) it is sufficiently addressed in my opinion.

Limitations

Checklist for review

Some things are not automated, and forgotten often. This list is a reminder for the reviewers.

• The bug fix is important enough to be backported? (label: 'backport requested')
• This PR affects the save game format? (label 'savegame upgrade')
• This PR affects the GS/AI API? (label 'needs review: Script API')
  • ai_changelog.hpp, gs_changelog.hpp need updating.
  • The compatibility wrappers (compat_*.nut) need updating.
• This PR affects the NewGRF API? (label 'needs review: NewGRF')
  • newgrf_debug_data.h may need updating.
  • PR must be added to API tracker