[gnome-builder] doc: add gdk3 to fixrefs paths

[Christian Hergert <chergert src gnome org>]

commit d706439fb1cd98244a779305106d1c8534c8abaf
Author: Christian Hergert <chergert redhat com>
Date:   Sat Nov 4 17:53:06 2017 -0700

    doc: add gdk3 to fixrefs paths

 doc/sdk/meson.build |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/doc/sdk/meson.build b/doc/sdk/meson.build
index 0f5bcf5..fd8bb05 100644
--- a/doc/sdk/meson.build
+++ b/doc/sdk/meson.build
@@ -46,6 +46,7 @@ gnome.gtkdoc('libide',
          '--extra-dir=@0@'.format(join_paths(glib_docpath, 'gio')),
          '--extra-dir=@0@'.format(join_paths(glib_docpath, 'glib')),
          '--extra-dir=@0@'.format(join_paths(glib_docpath, 'gobject')),
+         '--extra-dir=@0@'.format(join_paths(gtk_docpath, 'gdk3')),
          '--extra-dir=@0@'.format(join_paths(gtk_docpath, 'gtk3')),
          '--extra-dir=@0@'.format(join_paths(libdazzle_docpath, 'libdazzle')),
          '--extra-dir=@0@'.format(join_paths(json_docpath, 'json-glib')),