HDFS-9273. Moving to 2.6.3 CHANGES section to reflect the backport.

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -33,9 +33,6 @@ Release 2.7.3 - UNRELEASED
     HDFS-9314. Improve BlockPlacementPolicyDefault's picking of excess
     replicas. (Xiao Chen via zhz)
 
-    HDFS-9273. ACLs on root directory may be lost after NN restart.
-    (Xiao Chen via cnauroth)
-
 Release 2.7.2 - UNRELEASED
 
   INCOMPATIBLE CHANGES
@@ -1190,6 +1187,9 @@ Release 2.6.3 - UNRELEASED
     HDFS-9470. Encryption zone on root not loaded from fsimage after NN
     restart. (Xiao Chen via wang)
 
+    HDFS-9273. ACLs on root directory may be lost after NN restart.
+    (Xiao Chen via cnauroth)
+
 Release 2.6.2 - 2015-10-28
 
   INCOMPATIBLE CHANGES