[pitivi] Fix undo of deleted clips.

[Edward Hervey <edwardrv src gnome org>]

commit 679e2fbe9caa34ef76acf532a232dcc1b8920179
Author: Alessandro Decina <alessandro d gmail com>
Date:   Wed Jun 10 17:04:08 2009 +0200

    Fix undo of deleted clips.

 pitivi/timeline/timeline_undo.py |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)
---
diff --git a/pitivi/timeline/timeline_undo.py b/pitivi/timeline/timeline_undo.py
index 3060267..7da5d72 100644
--- a/pitivi/timeline/timeline_undo.py
+++ b/pitivi/timeline/timeline_undo.py
@@ -59,19 +59,21 @@ class TimelineObjectAdded(UndoableAction):
 class TimelineObjectRemoved(UndoableAction):
     def __init__(self, timeline, timeline_object):
         self.timeline = timeline
-        self.timeline_object_copy = self._copyTimelineObject(timeline_object)
         self.timeline_object = timeline_object
+        self.timeline_object_copy = self._copyTimelineObject(timeline_object)
 
     def do(self):
         self.timeline.removeTimelineObject(self.timeline_object, deep=True)
         self._done()
 
     def undo(self):
-        self.timeline_object = self.timeline_object_copy
-        for track_object in self.timeline_object.track_objects:
+        temporary_timeline_object = \
+                self._copyTimelineObject(self.timeline_object_copy)
+        for track_object in temporary_timeline_object.track_objects:
             track, track_object.track = track_object.track, None
             track.addTrackObject(track_object)
-        self.timeline_object_copy = self._copyTimelineObject(self.timeline_object)
+
+        self.timeline_object.track_objects = temporary_timeline_object.track_objects
         self.timeline.addTimelineObject(self.timeline_object)
         self._undone()