wxGUI: forms - self._giface can be None

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@56218 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/gui_core/forms.py

@@ -656,7 +656,8 @@ class TaskFrame(wx.Frame):
             add = True
         else:
             add = False
-        self._giface.mapCreated.emit(name=name, ltype=ltype, add=add)
+        if self._giface:
+            self._giface.mapCreated.emit(name=name, ltype=ltype, add=add)
     
     def OnOK(self, event):
         """!OK button pressed"""