Import a test case from MySQL 5.7.19

The test is for a bug that was introduced in MySQL 5.7.18
but not MariaDB 10.2, because MariaDB did not merge the change
that was considered incomplete and too risky for a GA release:

Bug#23481444 OPTIMISER CALL ROW_SEARCH_MVCC() AND READ THE INDEX
APPLIED BY UNCOMMITTED ROWS

So, we are only merging the test changes from the bug fix in MySQL 5.7.19,
not any code changes:

commit 4f86aca37d551cc756d9187ec901f8c4a68a0543
Author: Thirunarayanan Balathandayuthapani <thirunarayanan.balathandayuth@oracle.com>
Date:   Wed Apr 26 11:10:41 2017 +0530

    Bug #25793677   INNODB: FAILING ASSERTION: CLUST_TEMPL_FOR_SEC || LEN

mysql-test/suite/gcol/r/gcol_bugfixes.result

@@ -576,6 +576,19 @@ SELECT 1 FROM t WHERE c GROUP BY b;
 COMMIT;
 DROP TABLE t;
 #
+# Bug #25793677	INNODB: FAILING ASSERTION: CLUST_TEMPL_FOR_SEC || LEN ....
+#
+CREATE TABLE v (
+a INT,
+c INT,
+b CHAR(2) GENERATED ALWAYS AS (a IN (1)) VIRTUAL,
+KEY(c,b(1))) charset utf8mb4;
+INSERT INTO v (a,c) VALUES (1,1);
+SELECT (SELECT MAX(c) FROM v);
+(SELECT MAX(c) FROM v)
+1
+DROP TABLE v;
+#
 # MDEV-9255 Add generation_expression to information_schema.columns.
 #
 CREATE TABLE gcol_t1 (

mysql-test/suite/gcol/t/gcol_bugfixes.test

@@ -537,6 +537,19 @@ SELECT 1 FROM t WHERE c GROUP BY b;
 COMMIT;
 DROP TABLE t;
 
+--echo #
+--echo # Bug #25793677	INNODB: FAILING ASSERTION: CLUST_TEMPL_FOR_SEC || LEN ....
+--echo #
+
+CREATE TABLE v (
+a INT,
+c INT,
+b CHAR(2) GENERATED ALWAYS AS (a IN (1)) VIRTUAL,
+KEY(c,b(1))) charset utf8mb4;
+INSERT INTO v (a,c) VALUES (1,1);
+SELECT (SELECT MAX(c) FROM v);
+DROP TABLE v;
+
 --echo #
 --echo # MDEV-9255 Add generation_expression to information_schema.columns.
 --echo #