[gnome-software] build: Ensure actually we use the gnome-desktop support if enabled

[Richard Hughes <rhughes src gnome org>]

commit cf3705a886c30100dab9e1b40051beb0d782bfc9
Author: Richard Hughes <richard hughsie com>
Date:   Fri May 19 18:35:19 2017 +0100

    build: Ensure actually we use the gnome-desktop support if enabled

 meson.build     |    1 +
 src/meson.build |    4 ++++
 2 files changed, 5 insertions(+), 0 deletions(-)
---
diff --git a/meson.build b/meson.build
index d2fff09..54f5b26 100644
--- a/meson.build
+++ b/meson.build
@@ -110,6 +110,7 @@ endif
 
 if get_option('enable-gnome-desktop')
   gnome_desktop = dependency('gnome-desktop-3.0', version : '>= 3.17.92')
+  conf.set('HAVE_GNOME_DESKTOP', 1)
 endif
 
 if get_option('enable-gtkspell')
diff --git a/src/meson.build b/src/meson.build
index 6159937..4f2c5e9 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -96,6 +96,10 @@ if get_option('enable-packagekit')
   gnome_software_dependencies += [packagekit]
 endif
 
+if get_option('enable-gnome-desktop')
+  gnome_software_dependencies += [gnome_desktop]
+endif
+
 executable(
   'gnome-software',
   resources_src,