[gnome-builder] flatpak: Check FlatpakInstallation pointer for NULL

[Matthew Leeds <mwleeds src gnome org>]

commit 20bb05e73a5e62ca111f3170c23aeb996dfda397
Author: Matthew Leeds <mleeds redhat com>
Date:   Mon Jan 30 16:07:20 2017 -0600

    flatpak: Check FlatpakInstallation pointer for NULL
    
    This prevents a segfault in the flatpak library.

 plugins/flatpak/gbp-flatpak-runtime-provider.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/plugins/flatpak/gbp-flatpak-runtime-provider.c b/plugins/flatpak/gbp-flatpak-runtime-provider.c
index 989906f..f237506 100644
--- a/plugins/flatpak/gbp-flatpak-runtime-provider.c
+++ b/plugins/flatpak/gbp-flatpak-runtime-provider.c
@@ -393,6 +393,9 @@ find_deploy_dir (GbpFlatpakRuntimeProvider *self,
       FlatpakInstallation *installation = installations[i];
       g_autoptr(FlatpakInstalledRef) ref = NULL;
 
+      if (installation == NULL)
+        continue;
+
       ref = flatpak_installation_get_installed_ref (installation,
                                                     FLATPAK_REF_KIND_RUNTIME,
                                                     name,