parsers.c: parse_manifest: fixing refcount of flags
When flags was DECREF'ed, scope was referencing to the outer variable,
outside of the block.
It was in fact always NULL: the real Python object was never decref'ed.
% replace file with dir
initializing destination source-hg repository
scanning source...
sorting...
converting...
2 add d file
1 replace with d dir
0 add d/a
% manifest of tip
644 d/a
1 files updated, 0 files merged, 0 files removed, 0 files unresolved