HADOOP-13080. Refresh time in SysInfoWindows is in nanoseconds. Contributed by Inigo Goiri

(cherry picked from commit c1cc6ac667e9e1b2ed58f16cb9fa1584ea54f0ac)
(cherry picked from commit a50dc05a60487b50b5e8e6f3c99673f18e9aad22)

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/SysInfoWindows.java

@@ -59,7 +59,7 @@ public class SysInfoWindows extends SysInfo {
 
   @VisibleForTesting
   long now() {
-    return System.nanoTime();
+    return Time.monotonicNow();
   }
 
   void reset() {