Fixed: deleting a parent issue may lead to a stale object error (#7920).

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@5285 e93f8b46-1217-0410-a6f0-8f06a7374b81

vendor/plugins/awesome_nested_set/lib/awesome_nested_set.rb

@@ -466,6 +466,9 @@ module CollectiveIdea #:nodoc:
               ["#{quoted_right_column_name} >= ?", right]
             )
           end
+          
+          # Reload is needed because children may have updated their parent (self) during deletion.
+          reload
         end
 
         # reload left, right, and parent