[dconf-editor] dconf-window.vala: Make --enable-experimental-non-null happier.

[Arnaud Bonatti <arnaudb src gnome org>]

commit 92409fedbe40c0b559d03d6472f1b4a3b4994d84
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Fri Aug 19 18:59:47 2016 +0200

    dconf-window.vala: Make --enable-experimental-non-null happier.

 editor/dconf-window.vala |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/editor/dconf-window.vala b/editor/dconf-window.vala
index f00de84..d172744 100644
--- a/editor/dconf-window.vala
+++ b/editor/dconf-window.vala
@@ -278,7 +278,7 @@ class DConfWindow : ApplicationWindow
     [GtkCallback]
     private bool on_key_press_event (Widget widget, Gdk.EventKey event)     // TODO better?
     {
-        string name = Gdk.keyval_name (event.keyval) ?? "";
+        string name = (!) (Gdk.keyval_name (event.keyval) ?? "");
 
         if ((event.state & Gdk.ModifierType.CONTROL_MASK) != 0)
         {
@@ -346,7 +346,12 @@ class DConfWindow : ApplicationWindow
                 return true;
             }
             else if (name == "Down")
-                return pathbar.open_child ((event.state & Gdk.ModifierType.SHIFT_MASK) != 0 ? null : 
current_path);
+            {
+                if ((event.state & Gdk.ModifierType.SHIFT_MASK) != 0)
+                    return pathbar.open_child (null);
+                else
+                    return pathbar.open_child (current_path);
+            }
         }
 
         /* don't use "else if", or some widgets will not be hidden on <ctrl>F10 or such things */