Bug 892837 - Support permissions in desktop webrt. r=myk

--HG--
rename : webapprt/content/mochitest.js => webapprt/content/mochitest-shared.js
Bug 892837 - Tests for desktop webrt permissions. r=myk
Bug 892837 - Add manifestURL to the webapp.json file. r=myk
Bug 903404 - Move toolkit/content/aboutNetworking.net to toolkit/themes/shared. r=gavin

--HG--
rename : toolkit/content/aboutNetworking.css => toolkit/themes/shared/aboutNetworking.css