Rename ValueSet* to HistogramSet*.

tracing/tracing/metrics/system_health/hazard_metric_test.html

Index: tracing/tracing/metrics/system_health/hazard_metric_test.html
diff --git a/tracing/tracing/metrics/system_health/hazard_metric_test.html b/tracing/tracing/metrics/system_health/hazard_metric_test.html
index f89d10f4aa1b1e20d5e5a98386629ee0c466b55d..893ee5d7dff4ef8f0fbc41c59e520e4a12ca5df0 100644
--- a/tracing/tracing/metrics/system_health/hazard_metric_test.html
+++ b/tracing/tracing/metrics/system_health/hazard_metric_test.html
@@ -8,7 +8,7 @@ found in the LICENSE file.
 <link rel="import" href="/tracing/core/test_utils.html">
 <link rel="import"
     href="/tracing/metrics/system_health/hazard_metric.html">
-<link rel="import" href="/tracing/value/value_set.html">
+<link rel="import" href="/tracing/value/histogram_set.html">
 
 <script>
 'use strict';
@@ -22,7 +22,7 @@ tr.b.unittest.testSuite(function() {
 
       customizeModelCallback(model);
     });
-    var values = new tr.v.ValueSet();
+    var values = new tr.v.HistogramSet();
     tr.metrics.sh.hazardMetric(values, model);
     return tr.b.getOnlyElement(values);
   }