Keyboard indicator icon missing in xfce panel

[Minium]

OS:
Xubuntu Trusty Tahr 14.04

Kernel:
3.13.0-23-generic #45

Symptom:
The icon of the keyboard applet in the xfce panel is missing. All of the options in the applet can
be controlled correctly, i.e. the character map, the keyboard layout and text entry settings.
The symptom exists since today. The applet didn't exist before.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: xfce4-panel 4.11.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-23.45-generic 3.13.8
Uname: Linux 3.13.0-23-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.14.1-0ubuntu1
Architecture: amd64
CurrentDesktop: XFCE
Date: Wed Apr 9 14:19:43 2014
ExecutablePath: /usr/bin/xfce4-panel
InstallationDate: Installed on 2014-04-02 (6 days ago)
InstallationMedia: Xubuntu 14.04 LTS "Trusty Tahr" - Daily amd64 (20140402)
SourcePackage: xfce4-panel
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[George Politis (gpolitis)]

I'm wondering if indicator-keyboard is compatible with Xfce. I've installed it manually and configured 2 languages, but selecting another language doesn't work. The xfce-kbd-plugin works fine.

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1305035

[Viktor Pal (deere)]

Hi I have the same problem in gnome-flashback (no icon) in Ubuntu 15.04.
Do you need new bug for this?