A recent change fixed performing HTTP PUT operations on the repository

resource without providing entire payloads for the form. It computed the

initial data based on a repository and populated the form, trying to

create a solid starting point.
This had a bug, though, that prevented actually submitting the

repository form via the administration page. It no longer considered

that some standard fields, like path, mirror_path, username, etc.,

might be submitted with an SCMTool prefix (e.g., git-mirror_path), and

this caused it to override these provided values with the initial data,

preventing these fields from being changed again.
This bug did not make it into a release, or into production on

RBCommons.
This change fixes the new logic on the repository form to check whether

the prefixed form of a key was posted on the form data before trying to

figure out a fallback value for it. If it's explicitly posted, we use

the existing value. Otherwise, we now normalize a prefixed form, if one

was provided, and then fall back on the initial value.

Unit tests passed.
I was able to successfully modify the formerly-broken fields for

several existing repositories.