webservices: get_groups_by_id requires institution

[Robert Lyon]

Currently the webservices method to fetch group information by id requires the group to have institution set.

Will need to be adjusted to allow for groups not attached to an institution.

[Aaron Wells (u-aaronw)]

I consider this one a bug rather than a feature, because it prevents you from being able to search for non-institution groups.

[Mahara Bot (dev-mahara)]

Patch for "master" branch: https://reviews.mahara.org/5746

[Russell Boyatt (russell-boyatt)]

If I understand the issue being reported here, the following change should address the issue - https://reviews.mahara.org/#/c/5746/.

* If no groups are specified in webservice call, then non-institution groups are retrieved (those groups with NULL institution in group table).

* For webservice access where no institution is set it now allows access to those groups (i.e. where WEBSERVICE_INSTITUTION is 'mahara' which is equivalent to NULL institution in group table).

Where a shortname is specified, the institution is still required.