Tests: adjusted todo in proxy_cache_error.t.
diff --git a/proxy_cache_error.t b/proxy_cache_error.t
index 6a02e0d..41f45be 100644
--- a/proxy_cache_error.t
+++ b/proxy_cache_error.t
@@ -81,8 +81,8 @@
# and rc = NGX_HTTP_GATEWAY_BAD_GATEWAY; after revision ad3f342f14ba046c this
# will result in ngx_http_finalize_request(NGX_HTTP_GATEWAY_BAD_GATEWAY),
# leading to an attempt to return additional error response and
-# the "header already sent" alert
+# the "header already sent" alert; fixed in 93abb5a855d6
-$t->todo_alerts();
+$t->todo_alerts() unless $t->has_version('1.13.9');
###############################################################################
