don't ignore status and sysmsg in group msg handler

[3dik]

When I receive "status" or "sysmsg" messages, they are not forwarded to the callback object because each message of type "groupchat" is processed by GroupXMPPMessageHandler if its node contains an "xmlns" attribute. Compare the method _handle_kik_event. At least on my setup, many, if not all, received messages do contain that "xmlns" attribute. For example:

• other user joined
• other user left
• other user was invited by yet another user
• other user was removed by yet another user

I did not really understand the iPad-specific edge case. Is this outdated by 9ea8795063a353a212b? That commit removed the namespace check for "kik:groups".

Anyway, GroupXMPPMessageHandler and XMPPMessageHandler already have redundant code for IncomingGroupChatMessage and IncomingGroupIsTyping. So I thought that just copying the other two if branches might be fine in the context of this PR.

I don't know if there are more, equivalent bugs.

[tomer8007]

Yes, the ideal is to get rid of the xmlns-based dispatching and dispatch by type instead. Then we can merge the generic XMPPMessageHandler with _handle_kik_event.

Thanks for pointing it out, anyway. I always wanted to delete the xmlns condition.