[evince] application: parent the about dialog to the currently active window

[Carlos Garcia Campos <carlosgc src gnome org>]

commit f1dacdd9b51888700e5c32bb5f944c1810278a63
Author: Cosimo Cecchi <cosimo endlessm com>
Date:   Thu Jun 16 13:44:42 2016 -0700

    application: parent the about dialog to the currently active window
    
    Instead of letting it go unparented, which is discouraged and
    inconsistent with other similar apps.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=767747

 shell/ev-application.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/shell/ev-application.c b/shell/ev-application.c
index c8ec9c5..eb5a94b 100644
--- a/shell/ev-application.c
+++ b/shell/ev-application.c
@@ -974,6 +974,8 @@ app_about_cb (GSimpleAction *action,
               GVariant      *parameter,
               gpointer       user_data)
 {
+        EvApplication *application = user_data;
+
         const char *authors[] = {
                 "Martin Kretzschmar <m_kretzschmar gmx net>",
                 "Jonathan Blandford <jrb gnome org>",
@@ -1020,7 +1022,7 @@ app_about_cb (GSimpleAction *action,
                                      _(license[2]), "\n",
                                      NULL);
 
-        gtk_show_about_dialog (NULL,
+        gtk_show_about_dialog (gtk_application_get_active_window (GTK_APPLICATION (application)),
                                "name", _("Evince"),
                                "version", VERSION,
                                "copyright", _("© 1996–2014 The Evince authors"),