upload-pack: Check for NOT_SHALLOW flag before sending a shallow to the client.

A commit may have been put on the shallow list, and then reached from
another branch and marked NOT_SHALLOW without being removed from the
list.

Signed-off-by: Alexandre Julliard <julliard@winehq.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

upload-pack.c

@@ -565,7 +565,7 @@ static void receive_needs(void)
 			SHALLOW, NOT_SHALLOW);
 		while (result) {
 			struct object *object = &result->item->object;
-			if (!(object->flags & CLIENT_SHALLOW)) {
+			if (!(object->flags & (CLIENT_SHALLOW|NOT_SHALLOW))) {
 				packet_write(1, "shallow %s",
 						sha1_to_hex(object->sha1));
 				register_shallow(object->sha1);