Allow selected users to administer webform access groups

Problem/Motivation

The Webform access module allows groups of users to be assigned specific permissions to multiple webform nodes. Only users with the 'administer webform' permission can currently manage these groups. Ideally selected users should be able to administer users assigned to an access group.

Proposed resolution

Add admin users to access groups. Admin users will be able to add and remove user accounts from an access group. Admin users can only manage users and will not be able to change what Webform nodes or permissions assigned to an access group.

Remaining tasks

• Add webform_access_admin table
• Add update hook to create a new table
• Update access group form to include 'Administrators' element
• Update APIs to support admins
• Update webform_access.schema.yml
• Update 'Access group' (/admin/structure/webform/access/group/manage) listing to include admins
• Update demo to create admin accounts
• Add ‘Manage users’ to 'Access group' operations
• Update 'Access' tab (/admin/structure/webform/access/group/manage) to allow admins to view assigned groups
• Write tests
• Create a change record
• Tag new beta release

Notes

• Admin will not be automatically assigned as a user to an acess group
• Admin can only add and remove users. All other group settings will be hidden, this includes title, description, webforms, and permissions.
• Admins can only add users via the 'Webform: Access' tab (/admin/structure/webform/access/group/manage).

User interface changes

• Access group admins will be displayed on the group list and editable in the group edit form

API changes

TDB

Data model changes

• New 'webform_access_admin' table

Release notes snippet

TDB