DB-766 add reproducer

mysql-test/suite/tokudb.bugs/r/db766.result

+set default_storage_engine=TokuDB;
+drop table if exists t1;
+CREATE TABLE t1(c1 INT,c2 CHAR)PARTITION BY KEY(c1) PARTITIONS 5;
+insert INTO t1 values(1,1),(2,1),(2,2),(2,3);
+ALTER TABLE t1 ADD UNIQUE INDEX i1(c1);
+ERROR 23000: Can't write; duplicate key in table 't1'
+drop table t1;

mysql-test/suite/tokudb.bugs/t/db766.test

+# reproducer for DB-766
+source include/have_tokudb.inc;
+source include/have_partition.inc;
+set default_storage_engine=TokuDB;
+disable_warnings;
+drop table if exists t1;
+enable_warnings;
+CREATE TABLE t1(c1 INT,c2 CHAR)PARTITION BY KEY(c1) PARTITIONS 5;
+insert INTO t1 values(1,1),(2,1),(2,2),(2,3);
+--error ER_DUP_KEY
+ALTER TABLE t1 ADD UNIQUE INDEX i1(c1);
+drop table t1;
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