[mutter/wip/texture-purge-on-nvidia: 6/9] backends/native: update glyph cache on resume

[Ray Strode <halfline src gnome org>]

commit 6ff42c2ab2d1edff5bc937eb0f4cea1c9469bcf5
Author: Ray Strode <rstrode redhat com>
Date:   Tue Jan 15 10:29:55 2019 -0500

    backends/native: update glyph cache on resume
    
    As mentioned in a previous commit, the proprietary NVIDIA
    driver garbles memory on suspend. That behavior, means that
    clutter's glyph cache (which is stored in GPU memory) gets
    corrupted on suspend.
    
    This commit ensures the glyph cache is blown away when
    the logind session becomes active (on VT switch and resume).

 src/backends/native/meta-backend-native.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
---
diff --git a/src/backends/native/meta-backend-native.c b/src/backends/native/meta-backend-native.c
index f87c5a066..0730a4acb 100644
--- a/src/backends/native/meta-backend-native.c
+++ b/src/backends/native/meta-backend-native.c
@@ -653,7 +653,10 @@ void meta_backend_native_resume (MetaBackendNative *native)
   MetaIdleMonitor *idle_monitor;
 
   if (cogl_has_feature (cogl_context, COGL_FEATURE_ID_UNSTABLE_TEXTURES))
-    g_signal_emit_by_name (display, "gl-video-memory-purged");
+    {
+      clutter_clear_glyph_cache ();
+      g_signal_emit_by_name (display, "gl-video-memory-purged");
+    }
 
   meta_monitor_manager_kms_resume (monitor_manager_kms);