I'm using Ubuntu Precise with Gnome Shell on a Dell Latitude E6520 and I'm missing the battery status icon. When I run
gnome-power-statistics then the battery info is displayed correctly so I'm sure Linux and Gnome can see the battery (So there is no ACPI problem). But there simply is no indicator icon in the gnome shell menu bar.
In the Power settings the combo box Show battery status in the menu bar is always empty. I can choose between the values When battery is present, When battery is charging/in use and never but it doesn't matter what I select here, the icon never appears and when I exit the power settings and open it again then the combo box is again empty. I also used the command
dconf --watch / to see what this combo box changes in the dconf settings. No output at all. So for some reason this combo box is totally broken.
I also tried it with a completely new user with a fresh Gnome configuration. The battery status icon was there the first time I logged in but disappeared on second login.
I also tried upgrading Gnome to the version distributed by the Gnome 3 Team, doesn't help.
I'm out of options. Any ideas?