When marking a message as read as we're opening it from the message

list, don't "bother" sorting the messagelist again before opening the
message, it adds a _bit_ of slowness when we don't need it and
we'll sort again when we get back to the message list.

src/com/fsck/k9/activity/MessageList.java

@@ -830,7 +830,6 @@ public class MessageList
         if (!message.read)
         {
             message.read = true;
-            mHandler.sortMessages();
         }
     }