During play-testing we found that if a client crashes (looking at your client @LordAro :P), only the server knew the client left. When he returned, there were two people with the same name, triggering a panic that our code is buggy.

In a sense, it is, but not in the way people were thinking :P

Motivation / Problem

The code mixed up "client has quit but we already told everyone"
with "client lost connection, handle this".

Split up those two signals:
- CLIENT_QUIT means we told everyone and the connection is now dead
- CONNECTION_LIST means we should tell everyone we lost a client

To put it in different words:
https://github.com/OpenTTD/OpenTTD/blob/release/1.11/src/network/core/tcp_game.cpp#L54 is called when a connection is lost. It calls https://github.com/OpenTTD/OpenTTD/blob/release/1.11/src/network/network_server.cpp#L269 which said: owh, this status code? That means the clients were already informed! And didn't tell anyone about the loss of client.

Description

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