Implementing primiano's strategy (maintain a per-file list of edits) as a merge driver, so it should Just Work... if we're lucky. Ideally, this will only kick in if you're merging over the rename commit.
There will be some complication with moved files. Oh well.
Bonus: make it so rebasing / merging over the commit automatically first merges up to rename^, then rebases to rename, then to the head of the tracked branch.
Comment 1 by dcheng@chromium.org
, Dec 22 2016