Added new status variables:

feature_dynamic_columns,feature_fulltext,feature_gis,feature_locale,feature_subquery,feature_timezone,feature_trigger,feature_xml
Opened_views, Executed_triggers, Executed_events
Added new process status 'updating status' as part of 'freeing items'

mysql-test/r/features.result:
  Test of feature_xxx status variables
mysql-test/r/mysqld--help.result:
  Removed duplicated 'language' variable.
mysql-test/r/view.result:
  Test of opened_views
mysql-test/suite/rpl/t/rpl_start_stop_slave.test:
  Write more information on failure
mysql-test/t/features.test:
  Test of feature_xxx status variables
mysql-test/t/view.test:
  Test of opened_views
sql/event_scheduler.cc:
  Increment executed_events status variable
sql/field.cc:
  Increment status variable
sql/item_func.cc:
  Increment status variable
sql/item_strfunc.cc:
  Increment status variable
sql/item_subselect.cc:
  Increment status variable
sql/item_xmlfunc.cc:
  Increment status variable
sql/mysqld.cc:
  Add new status variables to 'show status'
sql/mysqld.h:
  Added executed_events
sql/sql_base.cc:
  Increment status variable
sql/sql_class.h:
  Add new status variables
sql/sql_parse.cc:
  Added new process status 'updating status' as part of 'freeing items'
sql/sql_trigger.cc:
  Increment status variable
sql/sys_vars.cc:
  Increment status variable
sql/tztime.cc:
  Increment status variable

sql/item_subselect.cc

@@ -220,6 +220,8 @@ bool Item_subselect::fix_fields(THD *thd_param, Item **ref)
   uint8 uncacheable;
   bool res;
 
+  status_var_increment(thd->status_var.feature_subquery);
+
   DBUG_ASSERT(fixed == 0);
   engine->set_thd((thd= thd_param));
   if (!done_first_fix_fields)