[gtk+] wayland: avoid an unnecessary g_list_length call

[Matthias Clasen <matthiasc src gnome org>]

commit 8ffecabd9382381769758add0ddc15ca090cc310
Author: Mohammed Sadiq <sadiq sadiqpk org>
Date:   Tue Jan 17 08:06:46 2017 +0530

    wayland: avoid an unnecessary g_list_length call
    
    https://bugzilla.gnome.org/show_bug.cgi?id=777363

 gdk/wayland/gdkdisplay-wayland.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gdk/wayland/gdkdisplay-wayland.c b/gdk/wayland/gdkdisplay-wayland.c
index d1f6e4e..4780546 100644
--- a/gdk/wayland/gdkdisplay-wayland.c
+++ b/gdk/wayland/gdkdisplay-wayland.c
@@ -552,7 +552,7 @@ _gdk_wayland_display_open (const gchar *display_name)
 
   /* Wait for initializing to complete. This means waiting for all
    * asynchrounous roundtrips that were triggered during initial roundtrip. */
-  while (g_list_length (display_wayland->async_roundtrips) > 0)
+  while (display_wayland->async_roundtrips != NULL)
     {
       if (wl_display_dispatch (display_wayland->wl_display) < 0)
         {