Merge branch 'bc/object-id'

Conversion from uchar[20] to struct object_id continues.

* bc/object-id: (53 commits)
  object: convert parse_object* to take struct object_id
  tree: convert parse_tree_indirect to struct object_id
  sequencer: convert do_recursive_merge to struct object_id
  diff-lib: convert do_diff_cache to struct object_id
  builtin/ls-tree: convert to struct object_id
  merge: convert checkout_fast_forward to struct object_id
  sequencer: convert fast_forward_to to struct object_id
  builtin/ls-files: convert overlay_tree_on_cache to object_id
  builtin/read-tree: convert to struct object_id
  sha1_name: convert internals of peel_onion to object_id
  upload-pack: convert remaining parse_object callers to object_id
  revision: convert remaining parse_object callers to object_id
  revision: rename add_pending_sha1 to add_pending_oid
  http-push: convert process_ls_object and descendants to object_id
  refs/files-backend: convert many internals to struct object_id
  refs: convert struct ref_update to use struct object_id
  ref-filter: convert some static functions to struct object_id
  Convert struct ref_array_item to struct object_id
  Convert the verify_pack callback to struct object_id
  Convert lookup_tag to struct object_id
  ...

refs.h

@@ -602,10 +602,10 @@ enum expire_reflog_flags {
  *     unlocked again.
  */
 typedef void reflog_expiry_prepare_fn(const char *refname,
-				      const unsigned char *sha1,
+				      const struct object_id *oid,
 				      void *cb_data);
-typedef int reflog_expiry_should_prune_fn(unsigned char *osha1,
-					  unsigned char *nsha1,
+typedef int reflog_expiry_should_prune_fn(struct object_id *ooid,
+					  struct object_id *noid,
 					  const char *email,
 					  timestamp_t timestamp, int tz,
 					  const char *message, void *cb_data);