Hi.

The recent USE_LANGUAGE changes have broken quite a few packages. I'm currently 
trying to correct the packages that broke in a recent bulk build that have
so far slipped attention (See pkg/33562, more to come), but it just occurred to
me that many of these packages shouldn't have to define USE_LANGUAGES
themselves.

I know that i'm a bit late with this, but there are some packages offering buildlink.mk3
files, where it is known beforehand that the dependant package needs a certain 
USE_LANGUAGES value. For instance, if a package .include's x11/qt3-libs/buildlink3.mk,
it is using c++ (Since qt3-libs is c++). 

Why not defining a USE_LANGUAGES in these buildlink.mk3 files? I know the net result
would probably be ugly if a package includes multiple buildlink files, but it would
probably have prevented a lot of breakage.