ref-filter: die on parse_commit errors

The tag-contains algorithm quietly returns "does not
contain" when parse_commit() fails. But a parse failure is
an indication that the repository is corrupt. We should die
loudly rather than producing a bogus result.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

ref-filter.c

@@ -1523,9 +1523,7 @@ static enum contains_result contains_test(struct commit *candidate,
 		return CONTAINS_YES;
 	}
 
-	if (parse_commit(candidate) < 0)
-		return CONTAINS_NO;
-
+	parse_commit_or_die(candidate);
 	return CONTAINS_UNKNOWN;
 }