Updated mediawiki/extensions
Project: mediawiki/extensions/Translate  f66c3685e2d22d1477de0c70c6489cb99fee4f28

Get rid of SingleFileBasedMessageGroup

As the current MediaWikiExtensionMessageGroup shows, it is not
property of a messageg group: we have both json and php files
supported at the same time.

Change-Id: I692d364c53bfd719025222755be1f94cbadeb300