HBASE-16300 LruBlockCache.CACHE_FIXED_OVERHEAD should calculate LruBlockCache size correctly

Signed-off-by: Yu Li <liyu@apache.org>
diff --git a/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/LruBlockCache.java b/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/LruBlockCache.java
index 2487aad..29c5922 100644
--- a/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/LruBlockCache.java
+++ b/hbase-server/src/main/java/org/apache/hadoop/hbase/io/hfile/LruBlockCache.java
@@ -914,7 +914,7 @@
   }
 
   public final static long CACHE_FIXED_OVERHEAD = ClassSize.align(
-      (3 * Bytes.SIZEOF_LONG) + (10 * ClassSize.REFERENCE) +
+      (4 * Bytes.SIZEOF_LONG) + (9 * ClassSize.REFERENCE) +
       (5 * Bytes.SIZEOF_FLOAT) + (2 * Bytes.SIZEOF_BOOLEAN)
       + ClassSize.OBJECT);