Fix potential for NoneType as player if Owner is null on non-player activator.

git-svn-id: svn://svn.code.sf.net/p/crossfire/code/maps/trunk@21627 282e977c-c81d-0410-88c4-b93c2d0d6712

ChangeLog

@@ -1,3 +1,6 @@
+2020-12-19 Daniel Hawkins:
+        * python/quests/QuestAdvance.py: Bail from method if non-player activator has no owner.
+
 2020-12-17  Nicolas Weeger
         * /scorn/houses/resir: Move exit under an extra grass column on the right, for coherence.
         * scorn/temples/valkyrie: Fix stairs coordinates.

python/quests/QuestAdvance.py

@@ -52,6 +52,9 @@ def handle():
     return
   # if a spell was used, then the killer is the spell object, find the owner
   if player.Type != Crossfire.Type.PLAYER:
+    # If the non-player has no owner, then no quest changes.
+    if player.Owner is None:
+      return
     player = player.Owner
 
   if player.Type != Crossfire.Type.PLAYER: