[libwnck] pager: add missing case to switch statement

[Alberts Muktupāvels <muktupavels src gnome org>]

commit bc08ed8d7dcb1ceeb9976a1b80b53205348f4309
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Thu Apr 27 15:02:57 2017 +0300

    pager: add missing case to switch statement

 libwnck/pager.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/libwnck/pager.c b/libwnck/pager.c
index 942c7a1..4437fb6 100644
--- a/libwnck/pager.c
+++ b/libwnck/pager.c
@@ -2141,6 +2141,8 @@ wnck_pager_scroll_event (GtkWidget      *widget,
             index = n_workspaces - 1;
           }
         break;
+
+      case GDK_SCROLL_SMOOTH:
       default:
         g_assert_not_reached ();
         break;