Right now it lives in //ui/chromeos/. However, it's only used in //ash. There are also many places in //ash and //chrome/browser that use it without #if defined(OS_CHROMEOS) guards.
Rather than wrapping a bunch of a11y code in #ifdefs I think this file should just move to //ash and be put in namespace ash.
Comment 1 by jamescook@chromium.org
, Jun 20 2016