[PATCH 5 of 8 RFC] memctx: add note about p2

[Sean Farley]

# HG changeset patch
# User Sean Farley <sean.michael.farley at gmail.com>
# Date 1403063706 25200
#      Tue Jun 17 20:55:06 2014 -0700
# Node ID 3c10f9fb5f87c984d1c9fc91c821f45fd29a1b93
# Parent  6f2891408ace48a633862fd2b3dfb0ade1ab99db
memctx: add note about p2

diff --git a/mercurial/context.py b/mercurial/context.py
--- a/mercurial/context.py
+++ b/mercurial/context.py
@@ -1650,11 +1650,11 @@ class memctx(committablectx):
         man = pctx.manifest().copy()
 
         for f, fnode in man.iteritems():
             p1node = nullid
             p2node = nullid
-            p = pctx[f].parents()
+            p = pctx[f].parents() # if file isn't in pctx, check p2?
             if len(p) > 0:
                 p1node = p[0].node()
                 if len(p) > 1:
                     p2node = p[1].node()
             man[f] = revlog.hash(self[f].data(), p1node, p2node)