That does include all of their unit tests code though. I wouldn't personally define unit tests as "core" framework code since I can deploy a Rails app without them (they never show up in a stack trace). It's going to come down to your own semantics since Rails wouldn't exist as it is today without them either.
Ahhh, you know what? I just realized I was confused: the diff for rails 4 was about +110,000 / -100,000, that's what I'm remembering that number from. My bad!
- Django - 215,000 LOC (.py)
- Ruby - 232,000 LOC (.rb)
- CakePHP - 240,000 LOC (.php)