Navigation keyboard shortcuts should be set for window management

[Jeremy Lincicome]

Keybindings such as Alt+F4 and Alt+Tab aren't working. In keyboard shortcuts, "Switch windows" and "Close window"are both disabled. At least those keybindings should be enabled. Without those keybindings, navigation for a screen reader user is a challenge.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: gnome-control-center 1:3.3.90-0ubuntu4
ProcVersionSignature: Ubuntu 3.2.0-18.28-generic 3.2.9
Uname: Linux 3.2.0-18-generic x86_64
ApportVersion: 1.94-0ubuntu1
Architecture: amd64
Date: Mon Mar 5 05:21:35 2012
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Beta amd64 (20120301)
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-control-center
UpgradeStatus: No upgrade log present (probably fresh install)
usr_lib_gnome-control-center:
 activity-log-manager-control-center 0.9.2-0ubuntu3
 deja-dup 21.90-0ubuntu1
 gnome-bluetooth 3.2.2-0ubuntu3
 indicator-datetime 0.3.90-0ubuntu1