Who what calls create session for a dedicated server?

[Fallonsnest]

For dedicated server there is a method for creating the session provided in the GameSession class:

AGameSession::RegisterServer

void ASwatGameSession::RegisterServer()
{
	TSharedPtr<const FUniqueNetId> UserId;

	auto OnlineSubsystem = IOnlineSubsystem::Get();
	if (OnlineSubsystem)
	{
		auto IdentityInterface = OnlineSubsystem->GetIdentityInterface();
		if (IdentityInterface.IsValid())
		{
			UserId = IdentityInterface->GetUniquePlayerId(0);
		}
	}

	CreateGameSession(UserId, SwatGameMode->GetClass(), GetWorld()->GetMapName());
}