[UI] Image tags are cleared after validation error

[Andrew Lazarev]

Steps to repro:

1. Go to image registry
2. Click "register image"
3. Add some tags
4. Click "Done" leaving "user name" empty

Expected result:
Validation error with all entered data saved.

Observed result:
Validation error, but all added tags are removed.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/77695

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/77695
Committed: https://git.openstack.org/cgit/openstack/savanna-dashboard/commit/?id=138175e2506cf8f040d878c885e43206e08f8bfe
Submitter: Jenkins
Branch: master

commit 138175e2506cf8f040d878c885e43206e08f8bfe
Author: Chad Roberts <email address hidden>
Date: Mon Mar 3 15:38:57 2014 -0500

    Fixing image tags after form validation error

    When editing image tags, the values displayed
    are now computed on the fly from the value, if any
    that was last entered (existing tags, or perhaps
    tags that were entered but submitted along with
    an incomplete form).

    Closes-bug: #1270965

    Change-Id: Iec9bfae8a0c0da34751ba95274dc58eb7bc09d2e