Bug#37069: Make federated disabled by default

The federated storage engine is now disabled by default.
mysql-test-run.pl is updated to enable it whenever it's required and available.

mysql-test/lib/mtr_cases.pl:
  Bug#37069: mysql-test-run.pl automatically enables federated 
  for federated related tests
sql/sql_plugin.cc:
  Bug#37069: federated is disabled by default

mysql-test/lib/mtr_cases.pl

@@ -773,6 +773,13 @@ sub collect_one_test_case($$$$$$$$$) {
 	if ( $::used_default_engine =~ /^innodb/i );
     }
 
+    #enable federated for this test
+    if ($tinfo->{'federated_test'})
+    {
+      push(@{$tinfo->{'master_opt'}}, "--loose-federated");
+      push(@{$tinfo->{'slave_opt'}}, "--loose-federated");
+    }
+
     if ( $tinfo->{'big_test'} and ! $::opt_big_test )
     {
       $tinfo->{'skip'}= 1;
@@ -891,6 +898,8 @@ our @tags=
  ["include/have_ndb_extra.inc", "ndb_extra", 1],
  ["include/ndb_master-slave.inc", "ndb_test", 1],
  ["require_manager", "require_manager", 1],
+ ["include/federated.inc", "federated_test", 1],
+ ["include/have_federated_db.inc", "federated_test", 1],
 );
 
 sub mtr_options_from_test_file($$) {

sql/sql_plugin.cc

@@ -1137,9 +1137,10 @@ int plugin_init(int *argc, char **argv, int flags)
   {
     for (plugin= *builtins; plugin->info; plugin++)
     {
-      /* by default, only ndbcluster is disabled */
+      /* by default, ndbcluster and federated are disabled */
       def_enabled=
-        my_strcasecmp(&my_charset_latin1, plugin->name, "NDBCLUSTER") != 0;
+        my_strcasecmp(&my_charset_latin1, plugin->name, "NDBCLUSTER") != 0 &&
+        my_strcasecmp(&my_charset_latin1, plugin->name, "FEDERATED") != 0;
       bzero(&tmp, sizeof(tmp));
       tmp.plugin= plugin;
       tmp.name.str= (char *)plugin->name;