Having studied Creative Writing and Journalism (and a few editing classes), I can tell you that will acquire editing tools taking either major, but the Journalism aspect of editing is different from that of creative writing, as they serve different puposes. While the first has to maintain structure, tone and content, the latter must reach the lowest common reader, maintain content but also stick to the point. Just try and think what you want to do in the long run, and choose accordingly. Good luck!