context: use native string when peeking in __dict__
# skip-blame because we're just adding a prefix on a string constant
Differential Revision: https://phab.mercurial-scm.org/D1893
bundlerepo: use native str when peeking in __dict__
# skip-blame since it's just a string constant prefix
Differential Revision: https://phab.mercurial-scm.org/D1892