Move HADOOP-5557 change log from 0.18.3 to 0.18.4.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/core/branches/branch-0.18@757908 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -20,6 +20,9 @@ Release 0.18.4 - Unreleased
     providing synchronized modification to the counter xmitsInProgress in
     DataNode. (hairong)
 
+    HADOOP-5557. Fixes some minor problems in TestOverReplicatedBlocks.
+    (szetszwo)
+
 Release 0.18.3 - 2009-01-27
 
   IMPROVEMENTS
@@ -166,9 +169,6 @@ Release 0.18.3 - 2009-01-27
 
     HADOOP-4924. Fixes a race condition in TaskTracker re-init. (ddas)
 
-    HADOOP-5557. Fixes some minor problems in TestOverReplicatedBlocks.
-    (szetszwo)
-
 Release 0.18.2 - 2008-11-03
 
   BUG FIXES