{% form_theme form "MopaBootstrapBundle:Form:fields.html.twig" %}
<form action="{{ path('sonata_user_change_password') }}" {{ form_enctype(form) }} method="POST" class="fos_user_change_password form-horizontal">
    {{ form_widget(form) }}
    <button type="submit" class="btn btn-danger pull-right"><i class="icon-lock icon-white glyphicon glyphicon-lock"></i>&nbsp;{{ 'change_password.submit'|trans({}, 'FOSUserBundle') }}</button>
</form>