Author: Shamim Rezaie
MDL-72078 editor_atto: Use role=application and aria-describedby in Atto
According to https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/Roles/Application_Role
WYSIWYG web editors are proper use of the application role.
http://git.moodle.org/gw?p=moodle.git;a=commit;h=e2150f7da04dd3ee06c2e3c3b8ae0f780e7bd790
http://github.com/moodle/moodle/commit/e2150f7da04dd3ee06c2e3c3b8ae0f780e7bd790
+ 4.0 en [richtexteditor,editor_atto]