Current pane's button in the breadcrumb is clickable

[Dario Bertini]

You can see this in the screenshot for the "mouse and touchpad" pane:

the breadcrumb lets you click on it, even if this doesn't accomplish any purpose

moreover, this is inconsistent with the appereance of the nautilus location's breadcrumb

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: gnome-control-center 1:3.3.92-0ubuntu2
ProcVersionSignature: Ubuntu 3.2.0-19.31-generic 3.2.12
Uname: Linux 3.2.0-19-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 1.94.1-0ubuntu2
Architecture: amd64
Date: Thu Mar 22 14:01:52 2012
InstallationMedia: Kubuntu 11.10 "Oneiric Ocelot" - Release amd64+mac (20111012)
SourcePackage: gnome-control-center
UpgradeStatus: Upgraded to precise on 2012-03-17 (4 days ago)
usr_lib_gnome-control-center:
 activity-log-manager-control-center 0.9.4-0ubuntu1
 deja-dup 21.90-0ubuntu1
 gnome-bluetooth 3.2.2-0ubuntu4
 indicator-datetime 0.3.92-0ubuntu1