Safe translation of "file missing" in JavaScript

File uploader button is not working when using django in Catalan, because the translation of "file missing" is breaking the Javascript code.

I propose to use this translation escaped. It should not be modified at the translation, as this text appears in another file, in normal html.
I'd rather use `{{ _('Text')|escapejs }}` or `{% filter escapejs %}{% trans "file missing" %}{% endfilter %}` syntax here