[dconf-editor] Vala 0.40 is required.

[Arnaud B. <arnaudb src gnome org>]

commit f1ead87dd6d56c6064ab561cbf235ca2d6efc3a7
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Wed Sep 5 17:12:52 2018 +0200

    Vala 0.40 is required.
    
    See issue #5.

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index 44a75d0..06a362a 100644
--- a/meson.build
+++ b/meson.build
@@ -26,7 +26,7 @@ dconf_editor_namespace = 'ca.desrt.dconf-editor'
 cc = meson.get_compiler('c')
 valac = meson.get_compiler('vala')
 
-vala_req_version = '>= 0.36.11'
+vala_req_version = '>= 0.40.0'
 
 assert(valac.version().version_compare(vala_req_version),
        'vala ' + vala_req_version + ' is required')