HUD and the Dash search box allow non-printable ASCII characters as input

[Alexandros]

It is possible to insert non-printable ASCII characters in the Dash search box and the HUD.

Steps to reproduce:
1. Open the HUD or the Dash search box.
2. Press Ctrl+ '?' or any letter key except of 'a', 'x', 'c'.
3. Non-printable ASCII characters "appear".

What should happen:
These characters should not be allowed to be entered as input.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: unity 5.12-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-24.39-generic 3.2.16
Uname: Linux 3.2.0-24-generic i686
NonfreeKernelModules: wl
ApportVersion: 2.0.1-0ubuntu8
Architecture: i386
CheckboxSubmission: 3b134398caa8b94b9080ca2d905beab4
CheckboxSystem: b845c366ea09c60efa3a45c1b5b21525
CompizPlugins: [core,composite,opengl,compiztoolbox,decor,vpswitch,snap,mousepoll,resize,place,move,wall,grid,regex,imgpng,session,gnomecompat,animation,fade,unitymtgrabhandles,workarounds,scale,expo,ezoom,unityshell]
Date: Fri Jun 1 20:21:15 2012
InstallationMedia: Ubuntu-Netbook 10.04 "Lucid Lynx" - Release i386 (20100429.4)
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=el_GR.UTF-8
 SHELL=/bin/bash
SourcePackage: unity
UpgradeStatus: Upgraded to precise on 2012-05-02 (30 days ago)

[Chris Sampson (chrsamp)]

This bug is reproduceable on the precise livecd. FWIW, it's not present in Unity 2D.