[gnome-software] data: Fix `@libexecdir@` substitution in external-appstream polkit file

[Richard Hughes <rhughes src gnome org>]

commit 57725dcd8aa6b8ac24fb209332fe4a493ab44bcd
Author: Philip Withnall <withnall endlessm com>
Date:   Tue Jul 30 16:18:00 2019 +0100

    data: Fix `@libexecdir@` substitution in external-appstream polkit file
    
    Commit 38529480f86be5b078f54739956a6c2e85e0bc72 broke the substitution
    of the `@libexecdir@` placeholder in the polkit file. Fix that by using
    `configure_file()` and then `i18n.merge_file()` in a two-step process.
    
    Signed-off-by: Philip Withnall <withnall endlessm com>

 data/meson.build                                                 | 9 +++++++--
 ...icy.in => org.gnome.software.external-appstream.policy.in.in} | 0
 2 files changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/data/meson.build b/data/meson.build
index 8e5443a8..06573881 100644
--- a/data/meson.build
+++ b/data/meson.build
@@ -11,12 +11,17 @@ if get_option('external_appstream')
   conf_data = configuration_data()
   conf_data.set('libexecdir', join_paths(get_option('prefix'),
                                          get_option('libexecdir')))
+  out = configure_file(
+    input : 'org.gnome.software.external-appstream.policy.in.in',
+    output : 'org.gnome.software.external-appstream.policy.in',
+    install: false,
+    configuration : conf_data,
+  )
   i18n.merge_file(
-    input : 'org.gnome.software.external-appstream.policy.in',
+    input : out,
     output : 'org.gnome.software.external-appstream.policy',
     po_dir: join_paths(meson.source_root(), 'po'),
     install: true,
     install_dir: join_paths(get_option('datadir'), 'polkit-1', 'actions'),
-    configuration : conf_data
   )
 endif
diff --git a/data/org.gnome.software.external-appstream.policy.in 
b/data/org.gnome.software.external-appstream.policy.in.in
similarity index 100%
rename from data/org.gnome.software.external-appstream.policy.in
rename to data/org.gnome.software.external-appstream.policy.in.in