Backport of fix made in 6.0-maria in revision guilhem@mysql.com-20081020202418-yay1h55w9ffagp42

sql/sql_class.cc:
  Backport of fix made in 6.0-maria in revision guilhem@mysql.com-20081020202418-yay1h55w9ffagp42
  (this undoes a change made in WL 3064 (the deadlock detector patch) which asserted in
  "./mtr --embedded innodb_mysql" in 6.0-maria)

sql/sql_class.cc

@@ -896,12 +896,13 @@ THD::~THD()
 #endif
   stmt_map.reset();                     /* close all prepared statements */
   DBUG_ASSERT(lock_info.n_cursors == 0);
-  ha_close_connection(this);
-  plugin_thdvar_cleanup(this);
 
   if (!cleanup_done)
     cleanup();
 
+  ha_close_connection(this);
+  plugin_thdvar_cleanup(this);
+
   DBUG_PRINT("info", ("freeing security context"));
   main_security_ctx.destroy();
   safeFree(db);