Backport proposal for "Attached file indicator"

[Geert Janssens]

Robert Fewell recently contributed work to the master branch to add a 
visual indicator to transactions when a file/uri is attached, and some 
further refinements in that area.

There is an enhancement request for this in bugzilla as well [1]

While our policy states new features should be added on the master 
branch only, I'm considering backporting a minimal base part of Roberts 
work to maint anyway. That is the indicator itself only. This is a 
relatively well contained bit of gui code that's not too complicated to 
review. I'm talking about commits 5bb53c044..5f75f106ee here. Robert 
made more improvements, but this minimal set would greatly increase the 
usefulness of the file association feature.

Any objections ?

Regards,

Geert

P.S. I asked for this on the bugreport as well, but didn't see any 
responses. Probably my request got lost in the noise.


[1] https://bugzilla.gnome.org/show_bug.cgi?id=744790