sha1_file.c: add lookup_replace_object_extended() to pass flags

Currently, there is only one caller to lookup_replace_object()
that can benefit from passing it some flags, but we expect
that there could be more.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

cache.h

@@ -773,6 +773,12 @@ static inline const unsigned char *lookup_replace_object(const unsigned char *sh
 		return sha1;
 	return do_lookup_replace_object(sha1);
 }
+static inline const unsigned char *lookup_replace_object_extended(const unsigned char *sha1, unsigned flag)
+{
+	if (!(flag & LOOKUP_REPLACE_OBJECT))
+		return sha1;
+	return lookup_replace_object(sha1);
+}
 
 /* Read and unpack a sha1 file into memory, write memory to a sha1 file */
 extern int sha1_object_info(const unsigned char *, unsigned long *);

sha1_file.c

@@ -2662,8 +2662,7 @@ void *read_sha1_file_extended(const unsigned char *sha1,
 	void *data;
 	char *path;
 	const struct packed_git *p;
-	const unsigned char *repl = (flag & LOOKUP_REPLACE_OBJECT)
-		? lookup_replace_object(sha1) : sha1;
+	const unsigned char *repl = lookup_replace_object_extended(sha1, flag);
 
 	errno = 0;
 	data = read_object(repl, type, size);