I tried Atom for ten minutes and then gave up on it because it made undesirable whitespace changes by default. Doing code formatting is fine; doing code format

I tried Atom for ten minutes and then gave up on it because it made undesirable whitespace changes by default. Doing code formatting is fine; doing code formatting on lines from a checkout that I didn't change is bad. Yes, the file should be reformatted. But let me know before doing it, so I can make a formatting-only commit so it's easier to review when I put up the PR.