largefiles: avoid printing messages while rebasing by "_lfstatuswriters" Putting "lambda *msg, **opts: None" (= avoid printing messages always) into "_lfstatuswriters" while rebasing makes explicit passing "printmessage = False" for "updatelfiles()" useless. This patch also removes setting/unsetting "repo._isrebasing" in "overriderebase", because there is no code path referring it.