cleanup: use enum, not uint, for enum variables

sql/sql_class.h

@@ -362,11 +362,13 @@ class Foreign_key: public Key {
   LEX_CSTRING ref_db;
   LEX_CSTRING ref_table;
   List<Key_part_spec> ref_columns;
-  uint delete_opt, update_opt, match_opt;
+  enum enum_fk_option delete_opt, update_opt;
+  enum fk_match_opt match_opt;
   Foreign_key(const LEX_CSTRING *name_arg, List<Key_part_spec> *cols,
 	      const LEX_CSTRING *ref_db_arg, const LEX_CSTRING *ref_table_arg,
               List<Key_part_spec> *ref_cols,
-	      uint delete_opt_arg, uint update_opt_arg, uint match_opt_arg,
+              enum_fk_option delete_opt_arg, enum_fk_option update_opt_arg,
+              fk_match_opt match_opt_arg,
 	      DDL_options ddl_options)
     :Key(FOREIGN_KEY, name_arg, &default_key_create_info, 0, cols, NULL,
          ddl_options),

storage/innobase/handler/handler0alter.cc

@@ -1383,7 +1383,6 @@ innobase_set_foreign_key_option(
 	ut_ad(!foreign->type);
 
 	switch (fk_key->delete_opt) {
-	// JAN: TODO: ? MySQL 5.7 used enum fk_option directly from sql_lex.h
 	case FK_OPTION_NO_ACTION:
 	case FK_OPTION_RESTRICT:
 	case FK_OPTION_SET_DEFAULT:
@@ -1395,6 +1394,8 @@ innobase_set_foreign_key_option(
 	case FK_OPTION_SET_NULL:
 		foreign->type = DICT_FOREIGN_ON_DELETE_SET_NULL;
 		break;
+	case FK_OPTION_UNDEF:
+		DBUG_ASSERT(0);
 	}
 
 	switch (fk_key->update_opt) {
@@ -1409,6 +1410,8 @@ innobase_set_foreign_key_option(
 	case FK_OPTION_SET_NULL:
 		foreign->type |= DICT_FOREIGN_ON_UPDATE_SET_NULL;
 		break;
+	case FK_OPTION_UNDEF:
+		DBUG_ASSERT(0);
 	}
 
 	return(innobase_check_fk_option(foreign));