Bug 1041663 - handle dragging the global webrtc sharing indicator, r=dolske.

--HG--
extra : rebase_source : 6f0185993355251b6c723acdffaf1fca8719ee18
Bug 1041685 - show hidpi icons in the mac global webrtc sharing indicator, r=dolske.

--HG--
extra : rebase_source : 6557cce5fdc7ea6412df536a3f06a71743115ebb
Bug 1041687 - replace place holder screensharing icons with final icons, r=dolske.

--HG--
extra : rebase_source : c04478577e1f37fb39a1884b2a0b2249ee76a829
Bug 1042163 - Visual issues with the global indicator for screen/device sharing, r=Gijs.

--HG--
extra : rebase_source : b9859df1822175a7ff322c08d76cb1f437775650
Bug 1046142 - Empty language to translate to drop down on localized builds, r=gavin.

--HG--
extra : rebase_source : 0d2c4d772a672a4b2f7db28ea5cf0905d58b03b1