[gnome-builder] flatpak: Avoid causing json-glib to print a warning

[Matthew Leeds <mwleeds src gnome org>]

commit 0928e27b24d9ec65cab305e5adeea142d3189d30
Author: Matthew Leeds <mleeds redhat com>
Date:   Mon Dec 19 22:21:53 2016 -0600

    flatpak: Avoid causing json-glib to print a warning
    
    This commit makes Builder avoid calling json_object_get_array_member
    when the member doesn't exist (when the flatpak manifest doesn't have
    nested modules), which avoids an unnecessary warning message.

 plugins/flatpak/gbp-flatpak-runtime.c |   12 ++++++++----
 1 files changed, 8 insertions(+), 4 deletions(-)
---
diff --git a/plugins/flatpak/gbp-flatpak-runtime.c b/plugins/flatpak/gbp-flatpak-runtime.c
index 3ea8315..03d6f55 100644
--- a/plugins/flatpak/gbp-flatpak-runtime.c
+++ b/plugins/flatpak/gbp-flatpak-runtime.c
@@ -121,10 +121,14 @@ manifest_has_multiple_modules (JsonObject *object)
   else
     {
       object = json_array_get_object_element (modules, 0);
-      modules = json_object_get_array_member (object, "modules");
-      if (modules == NULL)
-        return FALSE;
-      return (json_array_get_length (modules) > 0);
+      if (json_object_has_member (object, "modules"))
+        {
+          modules = json_object_get_array_member (object, "modules");
+          if (modules == NULL)
+            return FALSE;
+          return (json_array_get_length (modules) > 0);
+        }
+      return FALSE;
     }
 }