Bug report: https://bugzilla.wikimedia.org/show_bug.cgi?id=72704

Wikibase api modules need to be converted to have support for i18n (internationalization), which is new in MediaWiki: https://www.mediawiki.org/wiki/API/Architecture_work/i18n . There is a script, although not sure if it works for Wikibase. Otherwise, the task can be done manually or use a modified version of the script. For more information on Wikibase, see https://www.mediawiki.org/wiki/Wikibase

The time to complete the task depends how familiar you are with gerrit and vagrant: https://www.mediawiki.org/wiki/MediaWiki-Vagrant . Once one figures out how to do this and converts the first module, the rest are probably quick and easy to convert.

Your mentor for this task is the user aude (and others in the #wikidata irc channel and probably you can also ask the user anomie on irc).

Students are required to read Wikimedia's general instructions at https://www.mediawiki.org/wiki/Google_Code-in_2014#Instructions_for_GCI_students first.