Revert "MDEV-32235: mysql_json cannot be used on newly created table"

This reverts commit 22f3ebe4.

mysql-test/main/mysql_json_table_recreate.result

@@ -181,7 +181,12 @@ t1	CREATE TABLE `t1` (
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
 drop table t1;
 create table t1(j mysql_json);
-ERROR HY000: Cannot create table `test`.`t1`: Run mariadb-upgrade, to upgrade table with mysql_json type.
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `j` mysql_json /* JSON from MySQL 5.7 */ CHARACTER SET utf8mb4 COLLATE utf8mb4_bin DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
+drop table t1;
 create table `testjson` (
 `t` json /* JSON from MySQL 5.7*/ CHARACTER SET utf8mb4 COLLATE utf8mb4_bin NOT NULL
 ) ENGINE=InnoDB DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci;
@@ -206,16 +211,5 @@ testjson	CREATE TABLE `testjson` (
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COLLATE=latin1_swedish_ci
 drop table testjson;
 #
-# MDEV-32235: mysql_json cannot be used on newly created table
-#
-CREATE TABLE t(j mysql_json);
-ERROR HY000: Cannot create table `test`.`t`: Run mariadb-upgrade, to upgrade table with mysql_json type.
-CREATE TABLE IF NOT EXISTS t(j mysql_json);
-ERROR HY000: Cannot create table `test`.`t`: Run mariadb-upgrade, to upgrade table with mysql_json type.
-CREATE OR REPLACE TABLE t(j mysql_json);
-ERROR HY000: Cannot create table `test`.`t`: Run mariadb-upgrade, to upgrade table with mysql_json type.
-CREATE TEMPORARY TABLE t(j mysql_json);
-ERROR HY000: Cannot create table `test`.`t`: Run mariadb-upgrade, to upgrade table with mysql_json type.
-#
 # End of 10.5 tests
 #

mysql-test/main/mysql_json_table_recreate.test

@@ -97,8 +97,9 @@ drop table mysql_json_test_big;
 create table t1(j json);
 show create table t1;
 drop table t1;
---error ER_CANT_CREATE_TABLE
 create table t1(j mysql_json);
+show create table t1;
+drop table t1;
 # `json` type should not have character set and collation other than utf8mb4_bin
 --error ER_PARSE_ERROR
 create table `testjson` (
@@ -120,20 +121,6 @@ create table `testjson` (
 show create table testjson;
 drop table testjson;
 
-
---echo #
---echo # MDEV-32235: mysql_json cannot be used on newly created table
---echo #
-
---error ER_CANT_CREATE_TABLE
-CREATE TABLE t(j mysql_json);
---error ER_CANT_CREATE_TABLE
-CREATE TABLE IF NOT EXISTS t(j mysql_json);
---error ER_CANT_CREATE_TABLE
-CREATE OR REPLACE TABLE t(j mysql_json);
---error ER_CANT_CREATE_TABLE
-CREATE TEMPORARY TABLE t(j mysql_json);
-
 --echo #
 --echo # End of 10.5 tests
 --echo #

sql/sql_table.cc

@@ -3657,19 +3657,6 @@ mysql_prepare_create_table(THD *thd, HA_CREATE_INFO *create_info,
     if (sql_field->vcol_info)
       sql_field->flags&= ~NOT_NULL_FLAG;
 
-    if (sql_field->real_field_type() == MYSQL_TYPE_BLOB &&
-        thd->lex->sql_command == SQLCOM_CREATE_TABLE)
-    {
-      if (!strcmp(sql_field->type_handler()->name().ptr(), "MYSQL_JSON"))
-      {
-        my_printf_error(ER_CANT_CREATE_TABLE,
-                        "Cannot create table %`s.%`s: "
-                        "Run mariadb-upgrade, "
-                        "to upgrade table with mysql_json type.", MYF(0),
-                        alter_info->db.str, alter_info->table_name.str);
-        DBUG_RETURN(TRUE);
-      }
-    }
     /*
       Initialize length from its original value (number of characters),
       which was set in the parser. This is necessary if we're