[gnome-games] fullscreen-box: Remove unused signal handler

[Alexander Mikhaylenko <alexm src gnome org>]

commit 33f5fb1b24ac91e8b4fb9814a36fef83799b3fd3
Author: Alexander Mikhaylenko <exalm7659 gmail com>
Date:   Mon Aug 12 21:31:43 2019 +0500

    fullscreen-box: Remove unused signal handler
    
    Fix a runtime warning.

 data/ui/fullscreen-box.ui | 1 -
 1 file changed, 1 deletion(-)
---
diff --git a/data/ui/fullscreen-box.ui b/data/ui/fullscreen-box.ui
index 423a41dc..8c4b23df 100644
--- a/data/ui/fullscreen-box.ui
+++ b/data/ui/fullscreen-box.ui
@@ -4,7 +4,6 @@
   <template class="GamesFullscreenBox" parent="GtkEventBox">
     <property name="visible">True</property>
     <property name="events">pointer-motion-mask</property>
-    <signal name="notify::is-fullscreen" handler="on_fullscreen_changed"/>
     <signal name="motion-notify-event" handler="on_motion_event"/>
     <child>
       <object class="GtkOverlay" id="overlay">