Don't crash when entering the detailed view if the

activity which created the entry is no more installed.

sugar/datastore/datastore.py

@@ -108,10 +108,10 @@ class DSObject(object):
 
         if self.metadata['activity']:
             activity_info = activity.get_registry().get_activity(self.metadata['activity'])
-            activities.append(activity_info)
+            if activity_info:
+                activities.append(activity_info)
 
         mime_type = self.metadata['mime_type']
-        print mime_type
         if mime_type:
             activities_info = activity.get_registry().get_activities_for_type(mime_type)
             for activity_info in activities_info: