[1.0.2] Textarea ID incomplete + aria-describedby missing reference

Problem/Motivation

On a textarea error :

• its ID is "error-desc--", whatever
• its "aria-describedby" attribute does not reference both description and error

Steps to reproduce

1. Display a form with a required text area
2. Manually remove the "required" attribute to be able to submit the form

Proposed resolution

Working on a fix.