[tomboy] Avoid crash on empty notebook name

[Sanford Armstrong <sharm src gnome org>]

commit 3375eafa90a6872d5e797157f3a1eae9b30b5b8c
Author: Greg Poirier <grep binary-snobbery com>
Date:   Sun Jan 3 17:08:58 2010 -0600

    Avoid crash on empty notebook name
    
    Fixes GNOME Bug #602483 -- check for null/empty string on
    OnNotebookRowEdited.

 Tomboy/RecentChanges.cs |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/Tomboy/RecentChanges.cs b/Tomboy/RecentChanges.cs
index 58823cf..9e05486 100644
--- a/Tomboy/RecentChanges.cs
+++ b/Tomboy/RecentChanges.cs
@@ -682,7 +682,8 @@ namespace Tomboy
 
 		void OnNotebookRowEdited (object sender, Gtk.EditedArgs args)
 		{
-			if (Notebooks.NotebookManager.NotebookExists (args.NewText))
+			if (Notebooks.NotebookManager.NotebookExists (args.NewText) ||
+			    string.IsNullOrEmpty (args.NewText))
 				return;
 			var oldNotebook = GetSelectedNotebook ();
 			if (oldNotebook is Notebooks.SpecialNotebook)