[metacity] display: simplify meta_spew_event

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 08ee30d0b13a076cd8ecf1e72c16d07a341611cb
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Mon Feb 27 22:18:55 2017 +0200

    display: simplify meta_spew_event

 src/core/display.c |    7 ++-----
 1 files changed, 2 insertions(+), 5 deletions(-)
---
diff --git a/src/core/display.c b/src/core/display.c
index 043e059..bcee417 100644
--- a/src/core/display.c
+++ b/src/core/display.c
@@ -2721,7 +2721,6 @@ meta_spew_event (MetaDisplay *display,
   const char *name = NULL;
   char *extra = NULL;
   char *winname;
-  MetaScreen *screen;
 
   if (!meta_is_verbose())
     return;
@@ -3008,10 +3007,8 @@ meta_spew_event (MetaDisplay *display,
       break;
     }
 
-  screen = meta_display_screen_for_root (display, event->xany.window);
-
-  if (screen)
-    winname = g_strdup_printf ("root %d", screen->number);
+  if (event->xany.window == display->screen->xroot)
+    winname = g_strdup_printf ("root %d", display->screen->number);
   else
     winname = g_strdup_printf ("0x%lx", event->xany.window);