Updated mediawiki/extensions
Project: mediawiki/extensions/MobileFrontend  c89dcb4456ddf604dfd9ef678444a5873e3fd4cf

Hygiene: Cleanup drawer markup

* Remove unused classes
* Remove CSS rules which are covered by MediaWiki UI
* Use progressive anchor for sign up
* Make edit anonymously link progressive anchor

Change-Id: I3dbe3ddb9339eb16376d83c7db9ea354d10a2427