[metacity] surface-xrender: do not recreate picture when unmapped

[Alberts Muktupāvels <muktupavels src gnome org>]

commit a09f85a09628e0a238010122ebd0acef91cdaa32
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Fri Oct 11 16:10:38 2019 +0300

    surface-xrender: do not recreate picture when unmapped

 src/compositor/meta-surface-xrender.c | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/src/compositor/meta-surface-xrender.c b/src/compositor/meta-surface-xrender.c
index ece44675..d770371e 100644
--- a/src/compositor/meta-surface-xrender.c
+++ b/src/compositor/meta-surface-xrender.c
@@ -132,9 +132,15 @@ static void
 meta_surface_xrender_pre_paint (MetaSurface *surface)
 {
   MetaSurfaceXRender *self;
+  MetaWindow *window;
 
   self = META_SURFACE_XRENDER (surface);
 
+  window = meta_surface_get_window (surface);
+
+  if (!meta_window_is_toplevel_mapped (window))
+    return;
+
   if (self->picture == None)
     self->picture = get_window_picture (self);
 }