When opening `shutter` it adds an indicator icon to the status bar.
However this doesn't happen (and an ugly default icon will be used) if
`shutter` can't find the `hicolor-icon-theme`. In such a case a warning
like this can be found in `stderr`:
```
Gtk-WARNING **: Could not find the icon 'image-png'. The 'hicolor' theme
was not found either, perhaps you need to install it.
```
As I don't think that we should force users to install this theme
globally and several other packages including `tor-browser`, `gparted`
or `clawsmail` add `hicolor-icon-theme` to their closure this seems to
be a fair measure.
However, none of the exporters I tried actually _worked_, but now
shutter at least returns an error to the user (pop-up UI element)
instead of silently hanging and only leaving messages on stdout/stderr
about the missing deps.
AFAICS, this changes the failure of Screenshot->Export functionality
from a packaging bug to an application bug (upstream).
Fixes this:
$ shutter
ERROR: imagemagick is missing --> aborting!
Due to 73f1f5eb39
("imagemagick: split dev output to fix #9604") which was committed in
the same period as shutter was added to nixpkgs.
Screenshot and annotation tool.
The application may complain about missing GConf dbus service[1], but it
still works (and remembers its settings, AFAICT).
[1]: The error message is (line wrapped):
GConf Error: Failed to contact configuration server; the most
common cause is a missing or misconfigured D-Bus session bus daemon. See
http://projects.gnome.org/gconf/ for information. (Details - 1: GetIOR
failed: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name
org.gnome.GConf was not provided by any .service files)
