[gthumb] list_tools: disconnect the signal handler only if it was set

[Paolo Bacchilega <paobac src gnome org>]

commit 854a6a8c964d672d37e3a81fb860ec38128d33d3
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Tue Oct 25 15:38:26 2011 +0200

    list_tools: disconnect the signal handler only if it was set

 extensions/list_tools/callbacks.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/extensions/list_tools/callbacks.c b/extensions/list_tools/callbacks.c
index 942baa8..ff2a5b1 100644
--- a/extensions/list_tools/callbacks.c
+++ b/extensions/list_tools/callbacks.c
@@ -89,7 +89,8 @@ typedef struct {
 static void
 browser_data_free (BrowserData *data)
 {
-	g_signal_handler_disconnect (gth_script_file_get (), data->scripts_changed_id);
+	if (data->scripts_changed_id != 0)
+		g_signal_handler_disconnect (gth_script_file_get (), data->scripts_changed_id);
 	g_free (data);
 }