fix set_server. keep compatibility with the gtk interface

lib/gui_qt.py

@@ -1450,7 +1450,11 @@ class ElectrumWindow(QMainWindow):
 
         try:
             cfg.set_key("proxy", { u'mode':unicode(proxy_mode.currentText()).lower(), u'host':unicode(proxy_host.text()), u'port':unicode(proxy_port.text()) }, True)
-            wallet.set_server(server, cfg.config["proxy"])
+            if cfg.config["proxy"]["mode"] != "none":
+                wallet.set_server(server, cfg.config["proxy"])
+            else:
+                wallet.set_server(server)
+                
         except Exception as err:
             QMessageBox.information(None, _('Error'), str(err), _('OK'))
             if parent == None:

lib/wallet.py

@@ -347,7 +347,7 @@ class Wallet:
     def is_up_to_date(self):
         return self.interface.responses.empty() and not self.interface.unanswered_requests
 
-    def set_server(self, server, proxy):
+    def set_server(self, server, proxy=None):
         # raise an error if the format isnt correct
         a,b,c = server.split(':')
         b = int(b)