[gnome-boxes] Support Color Scheme user preference

[Felipe Borges <felipeborges src gnome org>]

commit 553a819ae4e7255821268f350a509ca55d70ccff
Author: Maximiliano Sandoval R <msandova gnome org>
Date:   Thu Oct 14 14:18:44 2021 +0200

    Support Color Scheme user preference
    
    Requires a bump on the dependency once libhandy 1.6 is released.

 data/org.gnome.boxes.gschema.xml | 7 -------
 src/app-window.vala              | 3 +--
 src/meson.build                  | 2 ++
 3 files changed, 3 insertions(+), 9 deletions(-)
---
diff --git a/data/org.gnome.boxes.gschema.xml b/data/org.gnome.boxes.gschema.xml
index 2cc1c570..e3b0d317 100644
--- a/data/org.gnome.boxes.gschema.xml
+++ b/data/org.gnome.boxes.gschema.xml
@@ -47,13 +47,6 @@
         Whether Boxes is running for the first time
       </description>
     </key>
-    <key name="override-theme" type="b">
-      <default>true</default>
-      <summary>Override theme</summary>
-      <description>
-        Whether Boxes will override the user's theme
-      </description>
-    </key>
 
     <key name="shared-folders" type="s">
       <default>""</default>
diff --git a/src/app-window.vala b/src/app-window.vala
index 7ee13cbc..770cd436 100644
--- a/src/app-window.vala
+++ b/src/app-window.vala
@@ -140,8 +140,7 @@ public AppWindow (Gtk.Application app) {
         notify["ui-state"].connect (ui_state_changed);
 
         Gtk.Window.set_default_icon_name (Config.APPLICATION_ID);
-        var override_theme = settings.get_boolean ("override-theme");
-        Gtk.Settings.get_default ().gtk_application_prefer_dark_theme = override_theme;
+        Hdy.StyleManager.get_default ().color_scheme = PREFER_DARK;
 
         var provider = Boxes.load_css ("gtk-style.css");
         Gtk.StyleContext.add_provider_for_screen (Gdk.Screen.get_default (),
diff --git a/src/meson.build b/src/meson.build
index a84bde5d..def83629 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -143,6 +143,8 @@ dependencies = [
 spice = dependency ('spice-client-gtk-3.0', version: '>= 0.32')
 if spice.found ()
   vala_args += '--define=HAS_SPICE'
+  # FIXME Remove and bump version after libhandy 1.6 is released.
+  vala_args += '--disable-since-check'
 
   dependencies += [
     spice,