[gtk/matthiasc/for-master] Remove more mir remnants

[Matthias Clasen <matthiasc src gnome org>]

commit a73947e54f513cbafdaaafa427a5703a12b99aea
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Dec 28 21:52:34 2019 -0500

    Remove more mir remnants
    
    The mir backend was removed a while ago, so
    GDK_WINDOWING_MIR is never defined.

 gdk/gdkconfig.h.meson | 1 -
 gtk/gtkwindow.c       | 9 ---------
 2 files changed, 10 deletions(-)
---
diff --git a/gdk/gdkconfig.h.meson b/gdk/gdkconfig.h.meson
index e65e3c9408..80666b25f0 100644
--- a/gdk/gdkconfig.h.meson
+++ b/gdk/gdkconfig.h.meson
@@ -14,7 +14,6 @@ G_BEGIN_DECLS
 #mesondefine GDK_WINDOWING_BROADWAY
 #mesondefine GDK_WINDOWING_WAYLAND
 #mesondefine GDK_WINDOWING_WIN32
-#mesondefine GDK_WINDOWING_MIR
 
 #mesondefine GDK_RENDERING_VULKAN
 
diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index a7be84d871..608754aca9 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -103,10 +103,6 @@
 #include "broadway/gdkbroadway.h"
 #endif
 
-#ifdef GDK_WINDOWING_MIR
-#include "mir/gdkmir.h"
-#endif
-
 /**
  * SECTION:gtkwindow
  * @title: GtkWindow
@@ -4851,11 +4847,6 @@ gtk_window_should_use_csd (GtkWindow *window)
     }
 #endif
 
-#ifdef GDK_WINDOWING_MIR
-  if (GDK_IS_MIR_DISPLAY (gtk_widget_get_display (GTK_WIDGET (window))))
-    return TRUE;
-#endif
-
 #ifdef GDK_WINDOWING_WIN32
   if (g_strcmp0 (csd_env, "0") != 0 &&
       GDK_IS_WIN32_DISPLAY (gtk_widget_get_display (GTK_WIDGET (window))))