rebase: minor refactoring of _computeobsoletenotrebased This patch is a refactoring of the code skipping obsolete changesets already present in destination. It makes the following patches more legible. Instead of passing all the revs to be rebased to _computeobsoletenotrebased, we only pass the obsolete revisions of the rebaseset.

test-status: stabilize for no-execbit platforms The preceding #if conditional was the only modification to the file, so the "reverting file" line in the subsequent revert command was getting dropped.