angular-ui/bootstrap — pull request #2866 by KillaBee1985 (2014-10-21 13:44:36+00:00)
Title: Add watcher to isDisabled to style disabled accordion-heading properly

Fixes [#2612](https://github.com/angular-ui/bootstrap/issues/2612)

When you use 'accordion-heading' directive it transcludes content. So we just need to add 'text-muted' class if isDisabled is true.