Fix collaboration call_async

Port to Python 3 via Six aa8a5e7 did introduce a regression during
activity collaboration on both sharing and joining.

Fixes https://github.com/sugarlabs/sugar-toolkit-gtk3/issues/406

src/sugar3/presence/activity.py

@@ -125,19 +125,27 @@ class Activity(GObject.GObject):
 
     def _start_tracking_properties(self):
         bus = dbus.SessionBus()
-        arg_dict = dict(reply_handler=self.__got_properties_cb,
-                        error_handler=self.__error_handler_cb)
         if six.PY2:
-            arg_dict = arg_dict.update(utf8_strings=True)
-
-        self._get_properties_call = bus.call_async(
-            self.telepathy_conn.requested_bus_name,
-            self.telepathy_conn.object_path,
-            CONN_INTERFACE_ACTIVITY_PROPERTIES,
-            'GetProperties',
-            'u',
-            (self.room_handle,),
-            arg_dict)
+            self._get_properties_call = bus.call_async(
+                self.telepathy_conn.requested_bus_name,
+                self.telepathy_conn.object_path,
+                CONN_INTERFACE_ACTIVITY_PROPERTIES,
+                'GetProperties',
+                'u',
+                (self.room_handle,),
+                reply_handler=self.__got_properties_cb,
+                error_handler=self.__error_handler_cb,
+                utf8_strings=True)
+        else:
+            self._get_properties_call = bus.call_async(
+                self.telepathy_conn.requested_bus_name,
+                self.telepathy_conn.object_path,
+                CONN_INTERFACE_ACTIVITY_PROPERTIES,
+                'GetProperties',
+                'u',
+                (self.room_handle,),
+                reply_handler=self.__got_properties_cb,
+                error_handler=self.__error_handler_cb)
 
         # As only one Activity instance is needed per activity process,
         # we can afford listening to ActivityPropertiesChanged like this.

src/sugar3/presence/buddy.py

@@ -164,20 +164,29 @@ class Buddy(BaseBuddy):
                                      dbus_interface=CONNECTION)
         self.contact_handle = handles[0]
 
-        arg_dict = dict(reply_handler=self.__got_properties_cb,
-                        error_handler=self.__error_handler_cb,
-                        byte_arrays = True)
         if six.PY2:
-            arg_dict = arg_dict.update(utf8_strings=True)
-
-        self._get_properties_call = bus.call_async(
-            connection_name,
-            connection.object_path,
-            CONN_INTERFACE_BUDDY_INFO,
-            'GetProperties',
-            'u',
-            (self.contact_handle,),
-            arg_dict)
+            self._get_properties_call = bus.call_async(
+                connection_name,
+                connection.object_path,
+                CONN_INTERFACE_BUDDY_INFO,
+                'GetProperties',
+                'u',
+                (self.contact_handle,),
+                reply_handler=self.__got_properties_cb,
+                error_handler=self.__error_handler_cb,
+                utf8_strings=True,
+                byte_arrays=True)
+        else:
+            self._get_properties_call = bus.call_async(
+                connection_name,
+                connection.object_path,
+                CONN_INTERFACE_BUDDY_INFO,
+                'GetProperties',
+                'u',
+                (self.contact_handle,),
+                reply_handler=self.__got_properties_cb,
+                error_handler=self.__error_handler_cb,
+                byte_arrays=True)
 
         self._get_attributes_call = bus.call_async(
             connection_name,