Add support for all channel types

osu.Game/Online/Chat/ChannelType.cs

@@ -5,7 +5,11 @@ namespace osu.Game.Online.Chat
 {
     public enum ChannelType
     {
+        Public,
+        Multiplayer,
+        Spectator,
+        Temporary,
         PM,
-        Public
+        Group,
     }
 }

osu.Game/Overlays/Chat/Tabs/ChannelTabControl.cs

@@ -56,12 +56,10 @@ protected override TabItem<Channel> CreateTabItem(Channel value)
         {
             switch (value.Type)
             {
-                case ChannelType.Public:
+                default:
                     return new ChannelTabItem(value) { OnRequestClose = tabCloseRequested };
                 case ChannelType.PM:
                     return new PrivateChannelTabItem(value) { OnRequestClose = tabCloseRequested };
-                default:
-                    throw new InvalidOperationException("Only TargetType User and Channel are supported.");
             }
         }