gtk: fix compilation warning with gtk 3.22.2

gdk_screen_get_width() is deprecated since gtk 3.22.2, use
gdk_monitor_get_geometry() instead if it's available.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 20161026152108.12364-1-berto@igalia.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

ui/gtk.c

@@ -912,9 +912,28 @@ static gboolean gd_motion_event(GtkWidget *widget, GdkEventMotion *motion,
 
     if (!qemu_input_is_absolute() && s->ptr_owner == vc) {
         GdkScreen *screen = gtk_widget_get_screen(vc->gfx.drawing_area);
+        int screen_width, screen_height;
+
         int x = (int)motion->x_root;
         int y = (int)motion->y_root;
 
+#if GTK_CHECK_VERSION(3, 22, 0)
+        {
+            GdkDisplay *dpy = gtk_widget_get_display(widget);
+            GdkWindow *win = gtk_widget_get_window(widget);
+            GdkMonitor *monitor = gdk_display_get_monitor_at_window(dpy, win);
+            GdkRectangle geometry;
+            gdk_monitor_get_geometry(monitor, &geometry);
+            screen_width = geometry.width;
+            screen_height = geometry.height;
+        }
+#else
+        {
+            screen_width = gdk_screen_get_width(screen);
+            screen_height = gdk_screen_get_height(screen);
+        }
+#endif
+
         /* In relative mode check to see if client pointer hit
          * one of the screen edges, and if so move it back by
          * 200 pixels. This is important because the pointer
@@ -928,10 +947,10 @@ static gboolean gd_motion_event(GtkWidget *widget, GdkEventMotion *motion,
         if (y == 0) {
             y += 200;
         }
-        if (x == (gdk_screen_get_width(screen) - 1)) {
+        if (x == (screen_width - 1)) {
             x -= 200;
         }
-        if (y == (gdk_screen_get_height(screen) - 1)) {
+        if (y == (screen_height - 1)) {
             y -= 200;
         }