object: convert parse_object* to take struct object_id

Make parse_object, parse_object_or_die, and parse_object_buffer take a
pointer to struct object_id.  Remove the temporary variables inserted
earlier, since they are no longer necessary.  Transform all of the
callers using the following semantic patch:

@@
expression E1;
@@
- parse_object(E1.hash)
+ parse_object(&E1)

@@
expression E1;
@@
- parse_object(E1->hash)
+ parse_object(E1)

@@
expression E1, E2;
@@
- parse_object_or_die(E1.hash, E2)
+ parse_object_or_die(&E1, E2)

@@
expression E1, E2;
@@
- parse_object_or_die(E1->hash, E2)
+ parse_object_or_die(E1, E2)

@@
expression E1, E2, E3, E4, E5;
@@
- parse_object_buffer(E1.hash, E2, E3, E4, E5)
+ parse_object_buffer(&E1, E2, E3, E4, E5)

@@
expression E1, E2, E3, E4, E5;
@@
- parse_object_buffer(E1->hash, E2, E3, E4, E5)
+ parse_object_buffer(E1, E2, E3, E4, E5)

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/log-tree.c b/log-tree.c
index 6532c89..a4ec11c 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -105,13 +105,13 @@ static int add_ref_decoration(const char *refname, const struct object_id *oid,
 			warning("invalid replace ref %s", refname);
 			return 0;
 		}
-		obj = parse_object(original_oid.hash);
+		obj = parse_object(&original_oid);
 		if (obj)
 			add_name_decoration(DECORATION_GRAFTED, "replaced", obj);
 		return 0;
 	}
 
-	obj = parse_object(oid->hash);
+	obj = parse_object(oid);
 	if (!obj)
 		return 0;
 
@@ -132,7 +132,7 @@ static int add_ref_decoration(const char *refname, const struct object_id *oid,
 		if (!obj)
 			break;
 		if (!obj->parsed)
-			parse_object(obj->oid.hash);
+			parse_object(&obj->oid);
 		add_name_decoration(DECORATION_REF_TAG, refname, obj);
 	}
 	return 0;