GlCollapsibleListbox lacks validation state

Description

The GlCollapsibleListbox component can often be used inside a form context, but we have no state property to use.

This forces the form to validate the state directly only on the GlFormGroup, but we don't get an invalid state on the actual dropdown. It would be ideal if we had a prop that could show the invalid state visually as we do on other components.

Sadly the accessible validation would be missing since there is no underlying form input, but that's a separate problem.

image

Figma file

View design specs in Figma →

Checklist

Make sure the following are completed before closing the issue:

  1. Assign the correct component label to this issue.
  2. Create an MR with the additions or updates needed.
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  4. When applicable, create an MR in Pajamas to update the demos. If you do not have capacity to complete the demos, create an issue in Pajamas and bring the issue to your team planning session for prioritization and scheduling. Mark the issue as related to this one.
  5. When applicable, create an MR in Pajamas to update the component status.
  6. When applicable, create an issue in Pajamas using the "Component Documentation" issue template to update guidelines. Ping a designer on your team for awareness and bring the issue to your team planning meeting for prioritization and scheduling.
  7. When applicable, create an issue in Pajamas using the "Figma update" issue template to update the Figma UI Kit. Ping a designer on your team for awareness and bring the issue to your team planning meeting for prioritization and scheduling.
  8. When introducing a major or breaking change, communicate the changes within the Engineering Week in Review.
  9. 🎉 Congrats, you made it! You can now close this issue.
Edited by Marina Mosti