Turning qc_title to varbinary in MySQL to make it consistent with the
rest of fields.
For Postgres:
- Setting 0 as default for qc_value and qc_namespace
- Changing data type of qc_namespace from SMALLINT to INT to make it
the same with MySQL/Sqlite
- Renaming index to make it the same with other schemas
- Setting empty string as default of qc_title
Bug: T230428
Bug: T164898
Change-Id: I81527121609014d29182ae735a2c1f532d7d4d2a
