GitLab

Add nickname column with VARCHAR type to masked_credit_card table, so
that we later could store synced response to this table and retrieve
nickname.

Also add migration function and corresponding unittests to migrate
older version database to this new schema.

The follow up will be:
1. Store the nickname from sync response to masked_credit_card table.
2. PersonalDataManager retrieves the nickname from table.

Bug: 1059087
Change-Id: Iaabd50099eb6d6d0af1740f3f5b24b5767b58c69
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2093011
Commit-Queue: Sujie Zhu <sujiezhu@google.com>
Reviewed-by: Dominic Battré <battre@chromium.org>
Reviewed-by: Cait Phillips <caitkp@chromium.org>
Reviewed-by: Jared Saul <jsaul@google.com>
Cr-Commit-Position: refs/heads/master@{#749795}