[polari/wip/fmuellner/werror] ci: Make compiler warnings fatal

[Florian Müllner <fmuellner src gnome org>]

commit ef6c8514e5f0e83eb75304c0ea13710733a3a85b
Author: Florian Müllner <fmuellner gnome org>
Date:   Thu Feb 28 01:15:58 2019 +0100

    ci: Make compiler warnings fatal
    
    https://gitlab.gnome.org/GNOME/polari/merge_requests/94

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index cf9da17..348fa41 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -53,7 +53,7 @@ flatpak:
         - flatpak-builder --stop-at=${FLATPAK_MODULE} app ${MANIFEST_PATH}
         # Make sure to keep this in sync with the Flatpak manifest, all arguments
         # are passed except the config-args because we build it ourselves
-        - flatpak build app meson --prefix=/app ${MESON_ARGS} _build
+        - flatpak build app meson --prefix=/app ${MESON_ARGS} --werror _build
         - flatpak build app ninja -C _build install
         - flatpak-builder --finish-only --repo=repo --default-branch=${BRANCH} app ${MANIFEST_PATH}
         # Run automatic tests inside the Flatpak env