[vte] regex: Fix crash on match_check

[Christian Persch <chpe src gnome org>]

commit dd31529f5a79b0018b9aff03beb0335c7e6b6c8f
Author: Christian Persch <chpe gnome org>
Date:   Thu Oct 15 20:28:16 2015 +0200

    regex: Fix crash on match_check
    
    Always pass non-NULL @tag.

 src/vte.cc |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)
---
diff --git a/src/vte.cc b/src/vte.cc
index e1b252c..5016d79 100644
--- a/src/vte.cc
+++ b/src/vte.cc
@@ -2117,9 +2117,12 @@ vte_terminal_match_check(VteTerminal *terminal, glong column, glong row,
                        NULL;
        } else {
                 gsize start, end;
+                int ltag;
+
                ret = vte_terminal_match_check_internal(terminal,
                                                         column, row + delta,
-                                                        tag, &start, &end);
+                                                        tag ? tag : &ltag,
+                                                        &start, &end);
        }
        _VTE_DEBUG_IF(VTE_DEBUG_EVENTS | VTE_DEBUG_REGEX) {
                if (ret != NULL) g_printerr("Matched `%s'.\n", ret);