context: possibly yield initial fctx in blockdescendants()
If initial 'fctx' has changes in line range with respect to its parents, we
yield it first. This makes 'followlines(..., descend=True)' consistent with
'descendants()' revset which yields the starting revision.
We reuse one iteration of blockancestors() which does exactly what we want.
In test-annotate.t, adjust 'startrev' in one case to cover the situation where
the starting revision does not touch specified line range.
# name space package to host third party extensions
from __future__ import absolute_import
import pkgutil
__path__ = pkgutil.extend_path(__path__, __name__)