ChatControl: Fix pylint errors

gajim/chat_control_base.py

@@ -338,6 +338,8 @@ def __init__(self, type_id, parent_win, widget_name, contact, acct,
         self.command_hits = []
         self.last_key_tabs = False
 
+        self.sendmessage = True
+
         con = app.connections[self.account]
         con.get_module('Chatstate').set_active(self.contact)