[dconf-editor] Fix test.

[Arnaud Bonatti <arnaudb src gnome org>]

commit 2a518f4d0f5c6cf1d4e91d1db3905357b3b1c9d8
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Tue Dec 12 01:43:41 2017 +0100

    Fix test.

 editor/meson.build |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/editor/meson.build b/editor/meson.build
index 3c67bc2..59cbae4 100644
--- a/editor/meson.build
+++ b/editor/meson.build
@@ -45,7 +45,7 @@ xmllint = find_program('xmllint', required : false)
 if xmllint.found()
   test('test_dtd', xmllint, args: ['--valid',
                                    '--noout', '--nowarning',
-                                   join_paths(dconf_editor_schemadir, gschema)])
+                                   join_paths(meson.current_source_dir(), gschema)])
 else
   message('xmllint not found, no gschema DTD verification')
 endif