[mutter] x11/window: Don't manage InputOnly windows

[Jonas Ådahl <jadahl src gnome org>]

commit 4d763e1828545e02f434d98f42229fff1517b6e2
Author: Rui Matos <tiagomatos gmail com>
Date:   Sun Oct 15 22:44:11 2017 +0200

    x11/window: Don't manage InputOnly windows
    
    This was dropped by mistake in commit
    f166240225b6ab110b091520103d0370d51899ac.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=788493

 src/x11/window-x11.c |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/src/x11/window-x11.c b/src/x11/window-x11.c
index 4885f5f..5a6f113 100644
--- a/src/x11/window-x11.c
+++ b/src/x11/window-x11.c
@@ -3039,6 +3039,12 @@ meta_window_x11_new (MetaDisplay       *display,
       goto error;
     }
 
+  if (attrs.class == InputOnly)
+    {
+      meta_verbose ("Not managing InputOnly windows\n");
+      goto error;
+    }
+
   if (is_our_xwindow (display, screen, xwindow, &attrs))
     {
       meta_verbose ("Not managing our own windows\n");