[glib] gproxyresolverportal: do not connect to session bus when not under flatpak

[Carlos Garcia Campos <carlosgc src gnome org>]

commit 7dcc09e58688ea4c538f77824268a35c9654f5e6
Author: Carlos Garcia Campos <cgarcia igalia com>
Date:   Mon Nov 27 11:32:49 2017 +0100

    gproxyresolverportal: do not connect to session bus when not under flatpak
    
    While gio module extension is loaded a new GProxyResolverPortal is
    created to query whether it's supported. We always return FALSE when not
    aunder flatpak, so we don't need to connect to the session bus in that
    case. Add a helper ensure_resolver_proxy() that returns TRUE when the
    proxy is created and use it in is_supported() instead of creating the
    proxy unconditionally in the instance initialization.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=790894

 gio/gproxyresolverportal.c |   25 ++++++++++++++++++++++---
 1 files changed, 22 insertions(+), 3 deletions(-)
---
diff --git a/gio/gproxyresolverportal.c b/gio/gproxyresolverportal.c
index c300ec3..d525800 100644
--- a/gio/gproxyresolverportal.c
+++ b/gio/gproxyresolverportal.c
@@ -42,9 +42,15 @@ G_DEFINE_TYPE_WITH_CODE (GProxyResolverPortal, g_proxy_resolver_portal, G_TYPE_O
                                                          "portal",
                                                          90))
 
-static void
-g_proxy_resolver_portal_init (GProxyResolverPortal *resolver)
+static gboolean
+ensure_resolver_proxy (GProxyResolverPortal *resolver)
 {
+  if (resolver->resolver)
+    return TRUE;
+
+  if (!glib_should_use_portal ())
+    return FALSE;
+
   resolver->resolver = gxdp_proxy_resolver_proxy_new_for_bus_sync (G_BUS_TYPE_SESSION,
                                                                    G_DBUS_PROXY_FLAGS_DO_NOT_AUTO_START,
                                                                    "org.freedesktop.portal.Desktop",
@@ -53,6 +59,13 @@ g_proxy_resolver_portal_init (GProxyResolverPortal *resolver)
                                                                    NULL);
 
   resolver->network_available = glib_network_available_in_sandbox ();
+
+  return resolver->resolver != NULL;
+}
+
+static void
+g_proxy_resolver_portal_init (GProxyResolverPortal *resolver)
+{
 }
 
 static gboolean
@@ -62,7 +75,7 @@ g_proxy_resolver_portal_is_supported (GProxyResolver *object)
   char *name_owner;
   gboolean has_portal;
 
-  if (!glib_should_use_portal () || !resolver->resolver)
+  if (!ensure_resolver_proxy (resolver))
     return FALSE;
 
   name_owner = g_dbus_proxy_get_name_owner (G_DBUS_PROXY (resolver->resolver));
@@ -83,6 +96,9 @@ g_proxy_resolver_portal_lookup (GProxyResolver *proxy_resolver,
   GProxyResolverPortal *resolver = G_PROXY_RESOLVER_PORTAL (proxy_resolver);
   char **proxy = NULL;
 
+  ensure_resolver_proxy (resolver);
+  g_assert (resolver->resolver);
+
   if (!gxdp_proxy_resolver_call_lookup_sync (resolver->resolver,
                                              uri,
                                              &proxy,
@@ -129,6 +145,9 @@ g_proxy_resolver_portal_lookup_async (GProxyResolver      *proxy_resolver,
   GProxyResolverPortal *resolver = G_PROXY_RESOLVER_PORTAL (proxy_resolver);
   GTask *task;
 
+  ensure_resolver_proxy (resolver);
+  g_assert (resolver->resolver);
+
   task = g_task_new (proxy_resolver, cancellable, callback, user_data);
   gxdp_proxy_resolver_call_lookup (resolver->resolver,
                                    uri,