Unity itself is deprecated, but the API is also supported by KDE and the GNOME Dock extension,
which means that it will be useful for a wide variety of distributions.
To get a progress bar, the system must have a blender.desktop file and libunity installed.
The need for libunity is annoying, but the only alternative would be to integrate a DBus library...
Reviewers: campbellbarton, brecht
Differential Revision: https://developer.blender.org/D3106
41149ca134