Bug 1049685 - [Tarako][Settings] Ringer's name overlay Alerts in Sound setting page

* Workaround for li button in shared/style/button.css. This should be backout once bug 1010675 landed.
Merge pull request #22818 from begeeben/1049685_ringers_name_overlay_master

Bug 1049685 - [Tarako][Settings] Ringer's name overlay Alerts in Sound setting page, r= Arthur Chen [:arthurcc]

* Workaround for li button in shared/style/button.css. This should be backout once bug 1010675 landed.