Let's ensure we do all architecture-dependant stuff inside
mkChromiumDerivation and not pass archInfo around, so we can properly
decouple it from the main function.
This partially reverts 8d54dc6d13.
The main reason for doing this is because the architecture information
is no longer required in Chromium 37, so let's uglify and XXX it in
common.nix and remove it once version 37 hits the stable channel.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
3d665679c1