statusicon: Don't use deprecated method gtk_menu_popup() for GTK3

Also replace void* with proper parameter types.

src/statusicon/statusicon.cc

@@ -69,8 +69,8 @@ enum {
 
 static void si_popup_timer_start (GtkStatusIcon * icon);
 static void si_popup_timer_stop (GtkStatusIcon * icon);
-static void si_menu_show (int x, int y, unsigned button, uint32_t time, void *);
-static void si_popup_hide (void * icon);
+static void si_menu_show (GtkStatusIcon * icon, GdkEventButton * event);
+static void si_popup_hide (GtkStatusIcon * icon);
 
 const char * const StatusIcon::defaults[] = {
     "scroll_action", aud::numeric_string<SI_CFG_SCROLL_ACTION_VOLUME>::str,
@@ -125,7 +125,7 @@ static gboolean si_cb_btpress (GtkStatusIcon * icon, GdkEventButton * event)
           if (event->state & GDK_SHIFT_MASK)
               aud_drct_pl_prev ();
           else
-              si_menu_show (event->x_root, event->y_root, event->button, event->time, icon);
+              si_menu_show (icon, event);
           break;
     }
 
@@ -212,7 +212,7 @@ static gboolean si_popup_show (void * icon)
     return true;
 }
 
-static void si_popup_hide (void * icon)
+static void si_popup_hide (GtkStatusIcon * icon)
 {
     if (POPUP_IS_ACTIVE)
     {
@@ -259,10 +259,14 @@ static gboolean si_cb_tooltip (GtkStatusIcon * icon, int x, int y, gboolean keyb
     return false;
 }
 
-static void si_menu_show (int x, int y, unsigned button, uint32_t time, void * evbox)
+static void si_menu_show (GtkStatusIcon * icon, GdkEventButton * event)
 {
-    GtkWidget * si_menu = (GtkWidget *) g_object_get_data ((GObject *) evbox, "menu");
-    gtk_menu_popup ((GtkMenu *) si_menu, nullptr, nullptr, nullptr, nullptr, button, time);
+    GtkMenu * si_menu = (GtkMenu *) g_object_get_data ((GObject *) icon, "menu");
+#ifdef USE_GTK3
+    gtk_menu_popup_at_pointer (si_menu, (const GdkEvent *) event);
+#else
+    gtk_menu_popup (si_menu, nullptr, nullptr, nullptr, nullptr, event->button, event->time);
+#endif
 }
 
 static void open_files ()