[gtksourceview] PrintCompositor: fix warning

[Sébastien Wilmet <swilmet src gnome org>]

commit 682f399f3635341be2d22eafb3f7d378ad24a774
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Sun Aug 9 17:29:09 2015 +0200

    PrintCompositor: fix warning

 gtksourceview/gtksourceprintcompositor.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gtksourceview/gtksourceprintcompositor.c b/gtksourceview/gtksourceprintcompositor.c
index e68c322..1905b59 100644
--- a/gtksourceview/gtksourceprintcompositor.c
+++ b/gtksourceview/gtksourceprintcompositor.c
@@ -1839,6 +1839,8 @@ setup_pango_layouts (GtkSourcePrintCompositor *compositor,
                         */
                        pango_layout_set_ellipsize (layout, PANGO_ELLIPSIZE_END);
                        break;
+               default:
+                       g_return_if_reached ();
        }
 
        set_layout_tab_width (compositor, layout);