[gnome-builder] build: set GSETTINGS_SCHEMA_DIR for tests

[Christian Hergert <chergert src gnome org>]

commit 9aecf0af9c4ddeefde4be81bde3a8e3575da20c5
Author: Christian Hergert <chergert redhat com>
Date:   Sun Sep 24 11:50:05 2017 -0700

    build: set GSETTINGS_SCHEMA_DIR for tests
    
    We need access to the uninstalled gsettings schemas when running tests.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=788089

 src/tests/meson.build |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/src/tests/meson.build b/src/tests/meson.build
index 2a5fe1d..255422c 100644
--- a/src/tests/meson.build
+++ b/src/tests/meson.build
@@ -5,6 +5,7 @@ ide_test_env = [
   'G_TEST_BUILDDIR=@0@'.format(meson.current_build_dir()),
   'G_DEBUG=gc-friendly',
   'GSETTINGS_BACKEND=memory',
+  'GSETTINGS_SCHEMA_DIR=@0@/data/gsettings:$(GSETTINGS_SCHEMA_DIR)'.format(meson.build_root()),
   'PYTHONDONTWRITEBYTECODE=yes',
   'MALLOC_CHECK_=2',
 #  'MALLOC_PERTURB_=$((${RANDOM:-256} % 256))',