Trigger connectionClosed() on dropped client connection.

This avoid get zombie client nodes in manager when the cluster fallback to
verification state.

git-svn-id: https://svn.erp5.org/repos/neo/trunk@2074 71dcc9de-d417-0410-9af5-da40c76e7ee4

neo/master/app.py

@@ -348,7 +348,9 @@ class Application(object):
                     if node.isStorage() or node.isClient():
                         node.notify(Packets.StopOperation())
                         if node.isClient():
-                            node.getConnection().abort()
+                            conn = node.getConnection()
+                            conn.abort()
+                            conn.getHandler().connectionClosed(conn)
 
                 # Then, go back, and restart.
                 return