[dconf-editor] Compile with --enable-experimental-non-null.

[Arnaud Bonatti <arnaudb src gnome org>]

commit cd0d5c5b18b9bb335b25235f6ce73044d6f28618
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Fri Mar 11 16:17:18 2016 +0100

    Compile with --enable-experimental-non-null.

 editor/Makefile.am |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/editor/Makefile.am b/editor/Makefile.am
index b1762fa..b82834c 100644
--- a/editor/Makefile.am
+++ b/editor/Makefile.am
@@ -7,7 +7,8 @@ dconf_editor_VALAFLAGS = \
        --pkg gmodule-2.0 \
        --pkg dconf \
        --gresources $(builddir)/dconf-editor.gresource.xml \
-       --target-glib $(GLIB_REQUIRED)
+       --target-glib $(GLIB_REQUIRED) \
+       --enable-experimental-non-null
 
 dconf_editor_LDADD = $(DCONF_EDITOR_LIBS)