mysql.json std_data files have wrong char_length for mysql.compression_dictionary.data

90307  8:50:17 [ 55%] main.dd_upgrade_test                     w5  [ fail ]
        Test ended at 2019-03-07 08:50:17

CURRENT_TEST: main.dd_upgrade_test
mysqltest: At line 648: Command "diff_files" failed with error 1. my_errno=175.
...
# Check SDI from mysql.ibd
--- /tmp/results/PS/mysql-test/std_data/dd/sdi/upgrade/mysql.json	2019-03-07 10:36:44.000000000 +0300
+++ /tmp/results/PS/mysql-test/var/tmp/5/sdi_dest//mysql.json	2019-03-07 11:50:14.748171220 +0300
@@ -22959,7 +22959,7 @@
                 "is_virtual": false,
                 "hidden": 1,
                 "ordinal_position": 4,
-                "char_length": 8,
+                "char_length": 65535,
                 "numeric_precision": 0,
                 "numeric_scale": 0,
                 "numeric_scale_null": true,
safe_process[26615]: Child process: 26616, exit: 1

190307  9:02:20 [ 68%] innodb.sdi                               w1  [ fail ]
        Test ended at 2019-03-07 09:02:20

CURRENT_TEST: innodb.sdi
mysqltest: At line 174: Command "diff_files" failed with error 1. my_errno=175.
...
# Check SDI from mysql.ibd
--- /tmp/results/PS/mysql-test/std_data/dd/sdi/innodb_sdi/mysql.json	2019-03-07 10:36:44.000000000 +0300
+++ /tmp/results/PS/mysql-test/var/tmp/1/sdi_dest//mysql.json	2019-03-07 12:02:16.193581574 +0300
@@ -22959,7 +22959,7 @@
                 "is_virtual": false,
                 "hidden": 1,
                 "ordinal_position": 4,
-                "char_length": 8,
+                "char_length": 65535,
                 "numeric_precision": 0,
                 "numeric_scale": 0,
                 "numeric_scale_null": true,
safe_process[17520]: Child process: 17521, exit: 1
...