If the default keyring is missing, then chromium at the 1st start
importunately requires the user to enter a password for the keyring.
pam_gnome-keyring allows you to automatically generate a keyring
with the user's password.

At the suggestion of Mikhail Efremov <sem@altlinux.org>
pam_gnome-keyring has been added to the general list,
since keyring can use not only chromium.