We're also using a heck of a lot of space on netbook screens for the toolbar with just a back button in it.  Might need to look at that design at some point.

A quick hack for 3.0 might be to check the monitor size, and reduce the minimum requested height for the icon list.

Created attachment 184262 [details] [review]
background: Make icon list smaller on netbooks

The default treeview is quite tall by default, and with the addition
of the shell's toolbar, the titlebar and the GNOME shell panel,
the background panel would be too tall for netbook computers.

This works around the issue by setting a smaller height request
for the icon list when the screen on which the panel will be shown
are no taller than 768 pixels.

Created attachment 184263 [details] [review]
alternative patch

Here is a variant which connects to realize, and doesn't have to iterate over all monitors.

Created attachment 184264 [details] [review]
background: Make icon list smaller on netbooks

The default treeview is quite tall by default, and with the addition
of the shell's toolbar, the titlebar and the GNOME shell panel,
the background panel would be too tall for netbook computers.

This works around the issue by setting a smaller height request
for the icon list when the screen on which the panel will be shown
are no taller than 768 pixels.