py3: use util.forcebytestr() to convert error messages to bytes
This makes the python 3 buildbot green again.
Differential Revision: https://phab.mercurial-scm.org/D4811
context: stop catching TypeError when converting hex nodeid to binary
It has been a programming error to pass a 40-character string that is
not a hex nodeid since
8b86acc7aa64 (context: drop support for looking
up context by ambiguous changeid (API), 2018-04-28), so we can just
let it raise a TypeError.
Differential Revision: https://phab.mercurial-scm.org/D4807
context: stop catching and re-raising FilteredRepoLookupError
FilteredRepoLookupError is only raised by changectx's constructor and
the higher-level scmutil.revsymbol(), so there's no need to catch it
in changectx's constructor.
Differential Revision: https://phab.mercurial-scm.org/D4806