[gtk+] testpopover: Use HeaderBar to get CSD decorations

[Daniel Boles <dboles src gnome org>]

commit 1e832b2e162786c57c09752811f916071d070eb9
Author: Daniel Boles <dboles src gnome org>
Date:   Sun Aug 13 20:15:36 2017 +0100

    testpopover: Use HeaderBar to get CSD decorations
    
    This helps test whether the Popover positioning gets messed up by the
    presence of CSD shadow or other accessories around the content area.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=786209

 tests/testpopover.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/tests/testpopover.c b/tests/testpopover.c
index 7747e05..19eff54 100644
--- a/tests/testpopover.c
+++ b/tests/testpopover.c
@@ -48,6 +48,7 @@ main (int argc, char *argv[])
   GtkWidget *label;
   GtkWidget *check;
   GtkWidget *combo;
+  GtkWidget *header_bar;
 
 #ifdef GTK_SRCDIR
   g_chdir (GTK_SRCDIR);
@@ -57,6 +58,10 @@ main (int argc, char *argv[])
 
   win = gtk_window_new (GTK_WINDOW_TOPLEVEL);
   gtk_window_set_default_size (GTK_WINDOW (win), 400, 600);
+  header_bar = gtk_header_bar_new ();
+  gtk_header_bar_set_show_close_button (GTK_HEADER_BAR (header_bar), TRUE);
+  gtk_window_set_titlebar (GTK_WINDOW (win), header_bar);
+  gtk_window_set_title (GTK_WINDOW (win), "Test GtkPopover");
   actions = g_simple_action_group_new ();
   g_action_map_add_action_entries (G_ACTION_MAP (actions), entries, G_N_ELEMENTS (entries), NULL);