revlog: add a ways to blacklist some revision when searching for a delta
This will be useful to recompute appropriate deltas one the fly during
censor/strip operation with revlog-v2.
Differential Revision: https://phab.mercurial-scm.org/D10799
{
"conduit_uri": "https://phab.mercurial-scm.org/api",
"phabricator.uri": "https://phab.mercurial-scm.org/",
"repository.callsign": "HG",
"arc.land.onto.default": "@",
"base": "hg:.^"
}