This is wrong, please revert. The passed in label is already translated. It
gets translated either because People (re-)installed the MIME type, or
because the user created a new attribute with a name in his native language.
This change don't allow attribute *name* localization (which is,
indeed, already localized).
This change allow label *formatting* localization.
Before it, all labels in whatever locale were all suffixed with ':'
without any form of localization.
No space before the :, when one is required in french, for instance.
Maybe for some language there is even no : needed or other form is
used instead.
That's the purpose of this change.
But maybe I've missed something.
