Cleaning-up shared executors use of metrics service.

Change-Id: I4293df87cd46e9f22cbdf03cfbced9a21ba85de7
diff --git a/utils/misc/src/main/java/org/onlab/util/SharedExecutors.java b/utils/misc/src/main/java/org/onlab/util/SharedExecutors.java
index d0e7ff1..e4f5e5b 100644
--- a/utils/misc/src/main/java/org/onlab/util/SharedExecutors.java
+++ b/utils/misc/src/main/java/org/onlab/util/SharedExecutors.java
@@ -95,9 +95,15 @@
                                                             "onos-pool-executor-%d")));
     }
 
-
-    public static void setCalculatePoolPerformance(boolean calculatePoolPerformance, MetricsService metricsService) {
-        poolThreadExecutor.setCalculatePoolPerformance(calculatePoolPerformance, metricsService);
+    /**
+     * Enables or disables calculation of the pool performance metrics. If
+     * the metrics service is not null metric collection will be enabled;
+     * otherwise it will be disabled.
+     *
+     * @param metricsService optional metric service
+     */
+    public static void setMetricsService(MetricsService metricsService) {
+        poolThreadExecutor.setMetricsService(metricsService);
     }
 
     /**