[polari] roomList: Don't try to move selection when roomCount is zero

[Florian Müllner <fmuellner src gnome org>]

commit cf6747420f67f9777eb3ba12cad91dc72b4e75ef
Author: Florian Müllner <fmuellner gnome org>
Date:   Wed Sep 17 04:35:07 2014 +0200

    roomList: Don't try to move selection when roomCount is zero
    
    There's nowhere to move in this case; fixes an exception when trying
    to access activeRoom.id.

 src/roomList.js |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/src/roomList.js b/src/roomList.js
index dfe2b68..71cc6ee 100644
--- a/src/roomList.js
+++ b/src/roomList.js
@@ -251,6 +251,9 @@ const RoomList = new Lang.Class({
     },
 
     _moveSelectionFromRow: function(row) {
+        if (this._roomManager.roomCount == 0)
+            return;
+
         let activeRoom = this._roomManager.getActiveRoom();
         let current = this._roomRows[activeRoom.id].widget;