[smuxi] Engine-Tests: offset is less confusing than index

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

commit 5546d78f311151ada0e48ad1267c73fa928f513c
Author: Mirco Bauer <meebey meebey net>
Date:   Wed Feb 26 22:40:49 2014 +0100

    Engine-Tests: offset is less confusing than index

 src/Engine/MessageBuffers/SqliteMessageBuffer.cs |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/Engine/MessageBuffers/SqliteMessageBuffer.cs 
b/src/Engine/MessageBuffers/SqliteMessageBuffer.cs
index c8cc377..429e596 100644
--- a/src/Engine/MessageBuffers/SqliteMessageBuffer.cs
+++ b/src/Engine/MessageBuffers/SqliteMessageBuffer.cs
@@ -44,9 +44,9 @@ namespace Smuxi.Engine
             }
         }
 
-        public override MessageModel this[int index] {
+        public override MessageModel this[int offset] {
             get {
-                return GetRange(index, 1).First();
+                return GetRange(offset, 1).First();
             }
             set {
                 throw new NotImplementedException();