--- a/mercurial/manifest.py	Tue Sep 20 12:24:01 2016 -0700
+++ b/mercurial/manifest.py	Tue Sep 20 12:24:01 2016 -0700
@@ -1049,6 +1049,9 @@
             self._mancache[node] = m
         return m
 
+    def add(self, m, transaction, link, p1, p2, added, removed):
+        return self._revlog.add(m, transaction, link, p1, p2, added, removed)
+
 class manifestctx(object):
     """A class representing a single revision of a manifest, including its
     contents, its parent revs, and its linkrev.