I have a fresh installation of Ubuntu Trusty Tahr, I've added russian layout in System settings > Region & Language > Input Sources. Also, I've installed gnome-tweak-tool, and set input source toggle hotkey to Ctrl+Shift. But still, the only way to change layout is by clicking keyboard layout indicator.
I have tried several fixes for 13.10 found on AskUbuntu, but no luck:
cat /etc/default/keyboard XKBLAYOUT="us,ru" XKBVARIANT="," XKBMODEL="pc105" XKBOPTIONS="grp:ctrl_shift_toggle,terminate:ctrl_alt_bksp,grp_led:scroll"