[gtk/ebassi/build-fixes: 1/3] build: Replace source_root()

[Emmanuele Bassi <ebassi src gnome org>]

commit bd772610b1d0fbbe836e158b0eb24be31ffd30ec
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Fri Dec 24 15:48:06 2021 +0000

    build: Replace source_root()
    
    Use project_source_root(), which replaces the deprecated source_root().

 demos/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/demos/meson.build b/demos/meson.build
index 550f90b0de..91eb3c465c 100644
--- a/demos/meson.build
+++ b/demos/meson.build
@@ -3,7 +3,7 @@ demo_profile = get_option('profile')
 
 demo_conf_h = declare_dependency(
   sources: custom_target('demo-header',
-    command: [gen_demo_header, meson.source_root(), demo_profile],
+    command: [gen_demo_header, meson.project_source_root(), demo_profile],
     capture: true,
     output: 'demo_conf.h',
     build_by_default: true,