[Buildstream SDK] Backport GTK startup assert fix

https://bugs.webkit.org/show_bug.cgi?id=273370

Unreviewed, backport a GTK patch fixing an assert being raised at startup in Wayland.

* Tools/buildstream/elements/sdk/gtk.bst:
* Tools/buildstream/patches/gtk/0001-wayland-Consistently-handle-enum-type.patch: Added.

Canonical link: https://commits.webkit.org/278086@main

Tools/buildstream/elements/sdk/gtk.bst

@@ -4,6 +4,8 @@ sources:
   url: gitlab_gnome_org:GNOME/gtk.git
   track: 4.*
   ref: 4.15.0-0-g1a3c5cf420392f76998974f54edc899e526b524d
+- kind: patch
+  path: patches/gtk/0001-wayland-Consistently-handle-enum-type.patch
 build-depends:
 - sdk-build-depends/sassc.bst
 - freedesktop-sdk.bst:public-stacks/buildsystem-meson.bst

Tools/buildstream/patches/gtk/0001-wayland-Consistently-handle-enum-type.patch

@@ -0,0 +1,35 @@
+From 007e7c68dce68c2dcced89a1af4759f1956d9ab7 Mon Sep 17 00:00:00 2001
+From: Alice Mikhaylenko <alicem@gnome.org>
+Date: Mon, 22 Apr 2024 17:18:11 +0400
+Subject: [PATCH] wayland: Consistently handle enum type
+
+Fixes https://gitlab.gnome.org/GNOME/gtk/-/issues/6649
+---
+ gdk/wayland/gdkdisplay-wayland.c | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/gdk/wayland/gdkdisplay-wayland.c b/gdk/wayland/gdkdisplay-wayland.c
+index 70107360fe..bd260967e6 100644
+--- a/gdk/wayland/gdkdisplay-wayland.c
++++ b/gdk/wayland/gdkdisplay-wayland.c
+@@ -1917,6 +1917,7 @@ apply_portal_setting (TranslationEntry *entry,
+       entry->fallback.s = g_intern_string (g_variant_get_string (value, NULL));
+       break;
+     case G_TYPE_INT:
++    case G_TYPE_ENUM:
+       entry->fallback.i = g_variant_get_int32 (value);
+       break;
+     case G_TYPE_BOOLEAN:
+@@ -2166,6 +2167,9 @@ set_value_from_entry (GdkDisplay       *display,
+         case G_TYPE_BOOLEAN:
+           g_value_set_boolean (value, entry->fallback.b);
+           break;
++        case G_TYPE_ENUM:
++          g_value_set_enum (value, entry->fallback.i);
++          break;
+         case G_TYPE_NONE:
+           if (g_str_equal (entry->setting, "gtk-fontconfig-timestamp"))
+             g_value_set_uint (value, (guint)entry->fallback.i);
+-- 
+2.44.0
+