[vte] widget: Also set n_regexes out param on early return

[Christian Persch <chpe src gnome org>]

commit 6ed2ed23e32da468cd94f4f7b4425cdca2fe674f
Author: Christian Persch <chpe src gnome org>
Date:   Wed Apr 29 15:00:17 2020 +0200

    widget: Also set n_regexes out param on early return

 src/vtegtk.cc | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/src/vtegtk.cc b/src/vtegtk.cc
index e95702b1..cda59271 100644
--- a/src/vtegtk.cc
+++ b/src/vtegtk.cc
@@ -2292,8 +2292,11 @@ vte_terminal_event_check_regex_array(VteTerminal *terminal,
                                      guint32 match_flags,
                                      gsize *n_matches)
 {
-        if (n_regexes == 0)
+        if (n_regexes == 0) {
+                if (n_matches)
+                        *n_matches = 0;
                 return nullptr;
+        }
 
         auto matches = vte::glib::take_free_ptr(g_new0(char*, n_regexes));
         if (!vte_terminal_event_check_regex_simple(terminal,