[pkg-cinnamon] Bug#853059: Confusing theme choosing interface when no previews are available

[Margarita Manterola]

Package: cinnamon-common
Version: 3.2.7-1
Severity: important

The new theme choosing interface in cinnamon has buttons that are 
supposed to show a preview of what the theme will look like so that the 
user has a bit more to go on when choosing than just the name of the 
theme.  This is nice but it has the problem that if there is no preview 
available, it shows just a gray rectangle that gives the impression that 
something is broken (i.e. it's not clear at all that this means "no 
preview available").

This happens on both the window manager ("metacity-1" theme directory) 
and the controls ("gtk-3.0" theme directory) options.  The other options 
get previews rendered automatically from the themes, so they are ok.

The solution to this is to include the thumbnails for the themes.  
Cinnamon already includes some thumbnails, e.g.:

/usr/share/cinnamon/thumbnails/metacity-1/Adwaita.png
/usr/share/cinnamon/thumbnails/metacity-1/AgingGorilla.png
/usr/share/cinnamon/thumbnails/metacity-1/Atlanta.png
/usr/share/cinnamon/thumbnails/metacity-1/Box.png
/usr/share/cinnamon/thumbnails/metacity-1/Bright.png
/usr/share/cinnamon/thumbnails/metacity-1/Crux.png
/usr/share/cinnamon/thumbnails/metacity-1/Esco.png
/usr/share/cinnamon/thumbnails/metacity-1/HighContrast.png
/usr/share/cinnamon/thumbnails/metacity-1/Metabox.png
/usr/share/cinnamon/thumbnails/metacity-1/README
/usr/share/cinnamon/thumbnails/metacity-1/Simple.png
/usr/share/cinnamon/thumbnails/metacity-1/unknown.png

Unfortunately, most of the themes shipped by Debian are not listed 
there. All themes shipped in Debian should have a thumbnail included.

-- 
Regards,
Marga