[blam] Don't crash if the channel is empty

[Carlos MartÃn Nieto <cmartin src gnome org>]

commit 8306e716a5a64342782afaf7c93e6bc78c09e447
Author: Carlos MartÃn Nieto <cmn dwim me>
Date:   Wed Jan 16 01:10:44 2013 +0100

    Don't crash if the channel is empty

 src/ItemList.cs |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/ItemList.cs b/src/ItemList.cs
index 7d8799d..84a35b4 100644
--- a/src/ItemList.cs
+++ b/src/ItemList.cs
@@ -92,7 +92,7 @@ namespace Imendio.Blam {
 			var start = iter;
 			do {
 				Item item = (Item)model.GetValue(iter, 0);
-				if (fn(item))
+				if (item != null && fn(item))
 					return true;
 
 				if (!Model.IterNext(ref iter))