localrepo: forcibly copy list of filecache keys On Python 3, keys() is more like iterkeys(), so we got in trouble for mutating the dict while we're iterating here. Since the list of caches should be relatively small, work around this difference by just forcing a copy of the key list.

localrepo: turn hook kwargs back into strs before calling hook It might be better to ensure that the hook kwargs dict only has str keys on Python 3. I'm torn.

localrepo: ensure transaction id is fully bytes on py3