Asset variables not works with CacheBusting

[vbartusevicius]

If I use assetic variables, like:

    {% javascripts
        ....
        'js/routes.js'
        'js/translations/ThemeBundle/{locale}.js'
        vars=['locale']
    %}

config.yml:

assetic:
    variables:
        locale: [en, ru, ee]

Everything works fine on assetic:dump -e prod - I get what's expected - asset names are suffixed with locale.

But as soon as I enable cache_busting:

assetic:
    workers:
        cache_busting: true
    variables:
        locale: [en, ru, ee]

And now on assetic:dump -e prod Im not getting any assets, suffixed by locale, all of them are suffixed only by cache_busting.

This error I get in log:

assetic.ERROR: The template "UserAdminBundle:Static:create.html.twig" contains an error: The template "js/translations/ServiceFrontendBundle/{locale}.js" contains the variable "locale", but was not given any value for it.

[vbartusevicius]

Sadly no one else experienced same issue - just stuck again here.
Problem appears when \Assetic\Factory\Worker\CacheBustingWorker::getHash tries to get $factory->getLastModified($asset), debugging this stuff I see there is populates vars array, but no values in values array.

Any hint? Someone?