[smuxi: 149/179] Frontend-GNOME: support unselecting the protocol in ServerWidget

[Mirco M. M. Bauer <mmmbauer src gnome org>]

commit ab7c9f511d64494d95da79cba5e751641c70ad69
Author: Mirco Bauer <meebey meebey net>
Date:   Mon May 29 20:41:39 2017 +0800

    Frontend-GNOME: support unselecting the protocol in ServerWidget

 src/Frontend-GNOME/Views/ServerWidget.cs |    6 ++++++
 1 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/src/Frontend-GNOME/Views/ServerWidget.cs b/src/Frontend-GNOME/Views/ServerWidget.cs
index f0d273b..8704030 100644
--- a/src/Frontend-GNOME/Views/ServerWidget.cs
+++ b/src/Frontend-GNOME/Views/ServerWidget.cs
@@ -47,6 +47,12 @@ namespace Smuxi.Frontend.Gnome
 
         public string Protocol {
             set {
+                if (value == null) {
+                    // clear selection
+                    f_ProtocolComboBox.Active = -1;
+                    return;
+                }
+
                 Gtk.ListStore store = (Gtk.ListStore) ProtocolComboBox.Model;
                 int protocolPosition = -1;
                 int j = 0;