Report error when trying to modify strings
Report error when trying to modify strings

Fixes bug 588038.

jessevdk/vala,xdave/pvala,themiwi/vala,GNOME/vala,Jc2k/vala,kamanashisroy/aroop,frida/vala,rvu95/vala,Distrotech/vala,Distrotech/vala,playya/vala,themiwi/vala,rvu95/vala,GNOME/vala,rvu95/vala,jessevdk/vala,frida/vala,tjol/vala-tjol,lovebug356/vala,frida/vala,kamanashisroy/aroop,GNOME/vala,flobrosch/vala-fixes,kamanashisroy/aroop,Jc2k/vala,Distrotech/vala,flobrosch/vala-fixes,playya/vala,flobrosch/vala-fixes,spidermonkdust/vala,tjol/vala-tjol,phako/vala,severinh/vala,GNOME/vala,tjol/vala-tjol,lovebug356/vala,spidermonkdust/vala,playya/vala,severinh/vala,frida/vala,themiwi/vala,jessevdk/vala,severinh/vala,phako/vala,spidermonkdust/vala,frida/vala