Updated mediawiki/extensions
Project: mediawiki/extensions/MobileFrontend  87d048cc8958d58378156412dbac8ce6170596b4

Cleanup: Introduce mobilediff.css

Currently a large chunk of watchlist.css is not used by the watchlist
Move it into mobilediff.css

Change-Id: Icf7b19cf7051896b15642ce22dbbb75c9479bf98