t / t4135 / diff-with backslash.diffon commit lock_packed_refs(): take a `packed_ref_store *` parameter (f512f0f)
   1--- post\image.txt.orig 2010-08-18 20:13:31.680002255 -0500
   2+++ post\image.txt      2010-08-18 20:13:31.680002255 -0500
   3@@ -1 +1 @@
   4-preimage
   5+postimage