regression: use doesn't work from mysql client

[sougou]

In the example, after resharding is done, I tried targeting shards, but it seems to have no effect.
@morgo We'll likely have to create patch for 6.0 after this is fixed.

mysql> use `customer:-80`
Database changed
mysql> select * from customer;
+-------------+--------------------+
| customer_id | email              |
+-------------+--------------------+
|           4 | dan@domain.com     |
|           1 | alice@domain.com   |
|           2 | bob@domain.com     |
|           3 | charlie@domain.com |
|           5 | eve@domain.com     |
+-------------+--------------------+
5 rows in set (0.00 sec)

mysql> use `customer:80-`
Database changed
mysql> select * from customer;
+-------------+--------------------+
| customer_id | email              |
+-------------+--------------------+
|           1 | alice@domain.com   |
|           2 | bob@domain.com     |
|           3 | charlie@domain.com |
|           5 | eve@domain.com     |
|           4 | dan@domain.com     |
+-------------+--------------------+
5 rows in set (0.00 sec)