@SBisson found that the Echo role (which now sets up cross-wiki notifications and includes centralauth) did not work unless he did
vagrant enable-role centralauth
Other people apparently didn't have this problem (though this isn't necessarily a surprise, since Puppet ordering that isn't explicitly defined can either be ill-defined or deliberately random).
Might be as simple as:
require ::role::centralauth
@SBisson suggested that T133451: Enabling the Echo Vagrant role doesn't work might be the same issue. Might as well put up a quick fix for this; shouldn't hurt regardless if this is the cause.
Turns out not to be a quick fix, since it causes a dependency cycle, which I don't yet see how to break.
I'm going to put this down again. Some more information would help (exactly what the failure is) if we work on it again. Echo's only Puppet-time usage of CentralAuth is migrate_user, which already has some dependencies to other parts of CentralAuth (via Pass 0).
==> default: Running provisioner: lsb_check... ==> default: Running provisioner: puppet... ==> default: Running Puppet with site.pp... ==> default: Info: Loading facts in /vagrant/puppet/modules/stdlib/lib/facter/puppet_vardir.rb ==> default: Info: Loading facts in /vagrant/puppet/modules/stdlib/lib/facter/root_home.rb ==> default: Info: Loading facts in /vagrant/puppet/modules/stdlib/lib/facter/facter_dot_d.rb ==> default: Info: Loading facts in /vagrant/puppet/modules/stdlib/lib/facter/pe_version.rb ==> default: Notice: Compiled catalog for mediawiki-vagrant.dev in environment production in 344.07 seconds ==> default: Info: Loading facts in /vagrant/puppet/modules/stdlib/lib/facter/puppet_vardir.rb ==> default: Info: Loading facts in /vagrant/puppet/modules/stdlib/lib/facter/root_home.rb ==> default: Info: Loading facts in /vagrant/puppet/modules/stdlib/lib/facter/facter_dot_d.rb ==> default: Info: Loading facts in /vagrant/puppet/modules/stdlib/lib/facter/pe_version.rb ==> default: Info: Applying configuration version '1461598030.0ca9607' ==> default: Error: Could not apply complete catalog: Found 1 dependency cycle: ==> default: (Exec[Create CentralAuth spoofuser table] => Mysql::Sql[Create CentralAuth spoofuser table] => Class[Role::Centralauth] => Class[Role::Echo] => Mediawiki::Wiki[fr] => Exec[frwiki_setup] => Exec[update_all_databases] => Exec[Pass 0 of CentralAuth] => Mediawiki::Maintenance[Pass 0 of CentralAuth] => Class[Role::Centralauth]) ==> default: Try the '--graph' option and opening the resulting '.dot' file in OmniGraffle or GraphViz