twitter/bootstrap — pull request #6351 by amertum (2012-12-20 10:56:35+00:00)
Title: add missing collapsed class on accordion-toggle element when hiding actives ones

We currently used accordion with background images showing the element as collapsed or active. We used the CSS expressions '.accordion-toggle' and '.accordion-toggle.collapsed' to display these background images but the second one was not created when clicking on not the same accordion toggle.

This is a reopen of https://github.com/twitter/bootstrap/pull/5667 on wip branch