Beta Feature: Remove mobile styling from mobile on desktop

* Avoid global style changes to buttons and to loading class
as used by Watchlist
* Fix styling of page list

See: https://www.mediawiki.org/wiki/
  Talk:Beta_Features/Nearby_Pages#Button_regressions

Change-Id: I222f398e76cf219a9319fe50ffe73c2ff5625023
Merge "Beta Feature: Remove mobile styling from mobile on desktop"