* Fix desktop-id notification edge case
* Extract-method platform_util::GetDesktopName()
This removes duplicated code from libnotify_notifications.cc
and atom/common/linux/application_info.cc.
* Check for empty case in GetDesktopName().
* Move GetDesktopName() to brightray::util
* Remove unnecessary changes in platform_util
* Add a brightray::platform_util namespace
