Unmark Ukrainian keyboard from 'login-allowed'.

BUG=325968
TEST=Manual test with Chrome OS on Linux.

Review URL: https://codereview.chromium.org/111223002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@239746 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 239746