rebase: clarify that commits that become empty are skipped Our message just said that it created no changes, but we didn't explicitly say that that meant that the the commit was not rebased. It also wasn't clear why it created no changes, so this patch also clarifies that that was because the changes were already in the destination. Differential Revision: https://phab.mercurial-scm.org/D5395

rebase: format commit in usual way when explaining that it became empty We use the _ctxdesc() for other similar messages, so it seems we should use it here too. Differential Revision: https://phab.mercurial-scm.org/D5394