[epiphany] Add captive portal helper

[Jan-Michael Brummer <jbrummer src gnome org>]

commit bc312dbad8a9936b45626458f0c8bcee7e392bde
Author: Jan-Michael Brummer <jan brummer tabos org>
Date:   Fri Jul 10 21:02:50 2020 +0200

    Add captive portal helper
    
    Fixes: https://gitlab.gnome.org/GNOME/epiphany/-/issues/1061

 src/ephy-shell.c | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)
---
diff --git a/src/ephy-shell.c b/src/ephy-shell.c
index d850b3f49..5558ea6d4 100644
--- a/src/ephy-shell.c
+++ b/src/ephy-shell.c
@@ -586,12 +586,33 @@ session_load_cb (GObject      *object,
   ephy_shell_startup_continue (ephy_shell_get_default (), ctx);
 }
 
+static void
+portal_check (EphyShell *shell)
+{
+  if (g_network_monitor_get_connectivity (ephy_shell_get_net_monitor (shell)) == 
G_NETWORK_CONNECTIVITY_PORTAL) {
+    EphyWindow *window = EPHY_WINDOW (gtk_application_get_active_window (GTK_APPLICATION (shell)));
+
+    ephy_window_load_url (window, "http://nmcheck.gnome.org/";);
+  }
+}
+
+static void
+connectivity_changed (GNetworkMonitor *monitor,
+                      GParamSpec      *pspec,
+                      EphyShell       *shell)
+{
+  portal_check (shell);
+}
+
 static void
 ephy_shell_activate (GApplication *application)
 {
   EphyShell *shell = EPHY_SHELL (application);
   EphyEmbedShell *embed_shell = EPHY_EMBED_SHELL (shell);
 
+  g_signal_connect (ephy_shell_get_net_monitor (shell), "notify::connectivity", G_CALLBACK 
(connectivity_changed), shell);
+  portal_check (shell);
+
   if (ephy_embed_shell_get_mode (embed_shell) == EPHY_EMBED_SHELL_MODE_AUTOMATION) {
     WebKitWebContext *web_context = ephy_embed_shell_get_web_context (embed_shell);
     g_signal_connect (web_context, "automation-started", G_CALLBACK (automation_started_cb), shell);