title: Problems with gnome-control-center after upgrading to Debian Jessie and Gnome 3.14.1
body: <p>I recently upgraded my Debian system to Jessie/stable (which also included an update to Gnome 3.14.1). Since then, when I run</p>
  
  <pre><code>gnome-control-center network
  </code></pre>
  
  <p>, I am getting the following errors:</p>
  
  <pre><code>(gnome-control-center:9451): GLib-CRITICAL **: g_variant_get_type: assertion 'value != NULL' failed
  
  (gnome-control-center:9451): GLib-CRITICAL **: g_variant_type_is_subtype_of: assertion 'g_variant_type_check (type)' failed
  
  (gnome-control-center:9451): GLib-CRITICAL **: g_variant_get_boolean: assertion 'g_variant_is_of_type (value, G_VARIANT_TYPE_BOOLEAN)' failed
  
  (gnome-control-center:9451): GLib-CRITICAL **: g_variant_get_type: assertion 'value != NULL' failed
  
  (gnome-control-center:9451): GLib-CRITICAL **: g_variant_type_is_subtype_of: assertion 'g_variant_type_check (type)' failed
  
  (gnome-control-center:9451): GLib-CRITICAL **: g_variant_get_boolean: assertion 'g_variant_is_of_type (value, G_VARIANT_TYPE_BOOLEAN)' failed
  </code></pre>
  
  <p>Also, the network information (IP/DNS/...) presented in the control center window differ from the actual settings - which nonetheless are working!</p>
  
  <p>Besides this, I get a similar output for</p>
  
  <pre><code>gnome-control-center sharing
  </code></pre>
  
  <p>:</p>
  
  <pre><code>(gnome-control-center:9875): GLib-CRITICAL **: g_variant_get_type: assertion 'value != NULL' failed
  
  (gnome-control-center:9875): GLib-CRITICAL **: g_variant_type_is_subtype_of: assertion 'g_variant_type_check (type)' failed
  
  (gnome-control-center:9875): GLib-CRITICAL **: g_variant_get_boolean: assertion 'g_variant_is_of_type (value, G_VARIANT_TYPE_BOOLEAN)' failed
  
  (gnome-control-center:9875): GLib-CRITICAL **: g_variant_unref: assertion 'value != NULL' failed
  
  (gnome-control-center:9875): sharing-cc-panel-WARNING **: couldn't list networks: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.SettingsDaemon.Sharing was not provided by any .service files
  
  (gnome-control-center:9875): sharing-cc-panel-WARNING **: couldn't list networks: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.SettingsDaemon.Sharing was not provided by any .service files
  
  (gnome-control-center:9875): sharing-cc-panel-WARNING **: couldn't list networks: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.SettingsDaemon.Sharing was not provided by any .service files
  </code></pre>
  
  <p>Here, all sharing options are disabled. And I cannot enable them.</p>
  
  <p>Any suggestions what might cause such behaviour?</p>