servo/servo — pull request #3859 by brunoabinader (2014-10-30 20:48:24+00:00)
Title: Cleanup Element's AttributeHandlers

Remove ```notify_attribute_{changed,removed}``` in favor of a unified ```notify_content_changed```. In the future, whether we decide to specialize ```document.content_changed()```, it'll be just a matter of adding a param.