[mutter] meson: Hide symbols by default in clutter

[Jonas Ådahl <jadahl src gnome org>]

commit adc5670ea9d0827c16528d8e236169982877c2e2
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Tue Jan 22 15:43:40 2019 +0100

    meson: Hide symbols by default in clutter
    
    Clutter exports symbols explicitly using `CLUTTER_EXPORT`, so everything should
    be hidden by default, unless exposed.
    
    Usage of `gnu_symbol_visibility` needs a version bump to meson 0.48.0
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/3955

 clutter/clutter/meson.build | 1 +
 meson.build                 | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/clutter/clutter/meson.build b/clutter/clutter/meson.build
index d17dcfb0b..e731e7e89 100644
--- a/clutter/clutter/meson.build
+++ b/clutter/clutter/meson.build
@@ -524,6 +524,7 @@ libmutter_clutter = shared_library(libmutter_clutter_name,
   c_args: clutter_c_args,
   include_directories: clutter_includes,
   dependencies: [clutter_deps],
+  gnu_symbol_visibility: 'hidden',
   link_with: [
     libmutter_cogl,
     libmutter_cogl_pango,
diff --git a/meson.build b/meson.build
index cb3e77a58..b5076ca50 100644
--- a/meson.build
+++ b/meson.build
@@ -1,6 +1,6 @@
 project('mutter', 'c',
   version: '3.31.4',
-  meson_version: '>= 0.46.0',
+  meson_version: '>= 0.48.0',
   license: 'GPLv2+'
 )