(refactor) common.sql.migration.find_migrate_repo never used with an argument.

[Ilya Pekelny]

If we look attentively to a `find_migrate_repo` usage we will see:
    $ grep -r "find_migrate_repo" keystone

    keystone/common/sql/migration.py: repo_path = find_migrate_repo()
    keystone/common/sql/migration.py: repo_path = find_migrate_repo()
    keystone/common/sql/migration.py: repo_path = find_migrate_repo()

The function never been used with an argument. What does it mean? This mean that the only line is needed in this function https://github.com/openstack/keystone/blob/master/keystone/common/sql/migration.py#L87. And at this point the function is redundant in the current state. Must be refactored.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/69593

[Dolph Mathews (dolph)]

("Fix Committed" is intended to reflect that the patch has been merged)

[Ilya Pekelny (i159)]

Thanks! I'm sorry.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/69593
Committed: https://git.openstack.org/cgit/openstack/keystone/commit/?id=7dcd6f03b88ac4c00e9c50e98f5318eac05527fd
Submitter: Jenkins
Branch: master

commit 7dcd6f03b88ac4c00e9c50e98f5318eac05527fd
Author: Ilya Pekelny <email address hidden>
Date: Mon Jan 27 19:40:54 2014 +0200

    Correct `find_migrate_repo` usage

    The `find_migrate_repo` function was never used with an argument although the
    function interface presupposes an optional argument named
    `package`.

    $ grep -r "find_migrate_repo" keystone

        keystone/common/sql/migration.py: repo_path = find_migrate_repo()
        keystone/common/sql/migration.py: repo_path = find_migrate_repo()
        keystone/common/sql/migration.py: repo_path = find_migrate_repo()

    The wrong function usage makes the function redundant (only one
    string is needed there, all others are never executed) and forces redundant
    code lines in other modules.
    Database migration functions must take an extension module object and handle
    a migration repository path with `find_migrate_repo` function.

    ::db_sync: [version, [package]]
    ::db_version: [package]
    ::db_version_control: [version, [package]]

    `find_migrate_repo` raises an error when the migrate repository path doesn't
    exist. The error should be handled to prevent further unexpected behaviour.

    Closes-Bug: #1273336
    Change-Id: Id62a1859a7e72139d25dfe91d29805660b4b7394