openseadragon/openseadragon — pull request #144 by acdha (2013-06-25 18:14:06+00:00)
Title: Safe cleanup in makeAjaxRequest error handler

Previously `request.onreadystatechange` was assigned an empty function on
success but null on failures, which breaks in IE (see
http://jsbin.com/ezozax/6/).

This patch simply mimics the success behaviour in the cleanup function

Closes #143