core/window: Implement GInitable

Currently, we will notify the display about a new window being created
during the constructed phase of the GObject. During this time,
property-change notifications are frozen by GObject, so we'll emit a few
::notify signals only after the window-created signal, although
the actual property change happened before that.

This caused confusion in gnome-shell code where a notify::skip-taskbar =
true emission was seen when the property already was true inside a
window-created handler before.

In order to fix that that, we notify the window creation
post-construction
of the GObject on GInitable.init vfunc

Details
https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/6119#note_1598983
Fixes https://gitlab.gnome.org/GNOME/gnome-shell/-/issues/6119

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2703>

3 files changed, 43 insertions, 18 deletions

diff --git a/src/core/window.c b/src/core/window.c
index 7faa3e95c..12121b455 100644
--- a/src/core/window.c
+++ b/src/core/window.c
@@ -158,12 +158,17 @@ static MetaWindow * meta_window_find_tile_match (MetaWindow   *window,
                                                  MetaTileMode  mode);
 static void update_edge_constraints (MetaWindow *window);
 
+static void initable_iface_init (GInitableIface *initable_iface);
+
 typedef struct _MetaWindowPrivate
 {
   MetaQueueType queued_types;
 } MetaWindowPrivate;
 
-G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (MetaWindow, meta_window, G_TYPE_OBJECT)
+G_DEFINE_ABSTRACT_TYPE_WITH_CODE (MetaWindow, meta_window, G_TYPE_OBJECT, 
+                                  G_ADD_PRIVATE (MetaWindow)
+                                  G_IMPLEMENT_INTERFACE (G_TYPE_INITABLE,
+                                                         initable_iface_init))
 
 enum
 {
@@ -1366,11 +1371,28 @@ meta_window_constructed (GObject *object)
     unminimize_window_and_all_transient_parents (window);
 
   window->constructing = FALSE;
+}
+
+static gboolean
+meta_window_initable_init (GInitable     *initable,
+                           GCancellable  *cancellable,
+                           GError       **error)
+{
+  MetaWindow *window = META_WINDOW (initable);
+  MetaDisplay *display = window->display;
 
   meta_display_notify_window_created (display, window);
 
   if (window->wm_state_demands_attention)
     g_signal_emit_by_name (display, "window-demands-attention", window);
+
+  return TRUE;
+}
+
+static void
+initable_iface_init (GInitableIface *initable_iface)
+{
+  initable_iface->init = meta_window_initable_init;
 }
 
 static gboolean
diff --git a/src/wayland/meta-window-wayland.c b/src/wayland/meta-window-wayland.c
index 3be11de40..b31d11d46 100644
--- a/src/wayland/meta-window-wayland.c
+++ b/src/wayland/meta-window-wayland.c
@@ -908,11 +908,12 @@ meta_window_wayland_new (MetaDisplay        *display,
   MetaWindowWayland *wl_window;
   MetaWindow *window;
 
-  window = g_object_new (META_TYPE_WINDOW_WAYLAND,
-                         "display", display,
-                         "effect", META_COMP_EFFECT_CREATE,
-                         "surface", surface,
-                         NULL);
+  window = g_initable_new (META_TYPE_WINDOW_WAYLAND,
+                           NULL, NULL,
+                           "display", display,
+                           "effect", META_COMP_EFFECT_CREATE,
+                           "surface", surface,
+                           NULL);
   wl_window = META_WINDOW_WAYLAND (window);
   set_geometry_scale_for_window (wl_window, wl_window->geometry_scale);
 
diff --git a/src/x11/window-x11.c b/src/x11/window-x11.c
index d69e2310b..1566e1e4a 100644
--- a/src/x11/window-x11.c
+++ b/src/x11/window-x11.c
@@ -3890,22 +3890,24 @@ meta_window_x11_new (MetaDisplay       *display,
 #ifdef HAVE_XWAYLAND
   if (meta_is_wayland_compositor ())
     {
-      window = g_object_new (META_TYPE_WINDOW_XWAYLAND,
-                             "display", display,
-                             "effect", effect,
-                             "attributes", &attrs,
-                             "xwindow", xwindow,
-                             NULL);    
+      window = g_initable_new (META_TYPE_WINDOW_XWAYLAND,
+                               NULL, NULL,
+                               "display", display,
+                               "effect", effect,
+                               "attributes", &attrs,
+                               "xwindow", xwindow,
+                               NULL);    
     }
   else
 #endif
     {
-      window = g_object_new (META_TYPE_WINDOW_X11,
-                             "display", display,
-                             "effect", effect,
-                             "attributes", &attrs,
-                             "xwindow", xwindow,
-                             NULL);
+      window = g_initable_new (META_TYPE_WINDOW_X11,
+                               NULL, NULL,
+                               "display", display,
+                               "effect", effect,
+                               "attributes", &attrs,
+                               "xwindow", xwindow,
+                               NULL);
     }
   if (existing_wm_state == IconicState)
     {