disconnect before deleting; we don't want to get informed of any changes from this point forward.

perhaps the cause of the "crash on lock" bug?
CCBUG:166802

svn path=/trunk/KDE/kdebase/workspace/libs/plasma/; revision=833582

containment.cpp

@@ -1079,6 +1079,7 @@ void ContainmentPrivate::toggleDesktopImmutability()
         handles.clear();
 
         foreach (AppletHandle* handle, h) {
+            handle->disconnect(q);
             handle->deleteLater();
         }
     }