Refactor NumericBuilder to HistogramBinBoundaries.

tracing/tracing/metrics/v8/gc_metric.html

Index: tracing/tracing/metrics/v8/gc_metric.html
diff --git a/tracing/tracing/metrics/v8/gc_metric.html b/tracing/tracing/metrics/v8/gc_metric.html
index 96a28608208e941424fb8d7b32512b1c8e886b83..7ea447828f9cc98bccf8208bab84f712853f9d17 100644
--- a/tracing/tracing/metrics/v8/gc_metric.html
+++ b/tracing/tracing/metrics/v8/gc_metric.html
@@ -37,18 +37,15 @@ tr.exportTo('tr.metrics.v8', function() {
       tr.v.Unit.byName.timeDurationInMs_smallerIsBetter;
   var percentage_biggerIsBetter =
       tr.v.Unit.byName.normalizedPercentage_biggerIsBetter;
-  var PERCENTAGE_BUILDER = tr.v.NumericBuilder.createLinear(
-      percentage_biggerIsBetter, tr.b.Range.fromExplicitRange(0, 1), 20);
 
-  var numericBuilder = new tr.v.NumericBuilder(
-      timeDurationInMs_smallerIsBetter, 0);
   // 0.1 steps from 0 to 20 since it is the most common range.
-  numericBuilder.addLinearBins(20, 200);
   // Exponentially increasing steps from 20 to 200.
-  numericBuilder.addExponentialBins(200, 100);
+  var CUSTOM_BOUNDARIES = tr.v.HistogramBinBoundaries.createLinear(0, 20, 200)
+    .addExponentialBins(200, 100);
 
   function createNumericForTopEventTime() {
-    var n = numericBuilder.build();
+    var n = new tr.v.Histogram(
+        timeDurationInMs_smallerIsBetter, CUSTOM_BOUNDARIES);
     n.customizeSummaryOptions({
         avg: true,
         count: true,
@@ -61,7 +58,8 @@ tr.exportTo('tr.metrics.v8', function() {
   }
 
   function createNumericForSubEventTime() {
-    var n = numericBuilder.build();
+    var n = new tr.v.Histogram(
+        timeDurationInMs_smallerIsBetter, CUSTOM_BOUNDARIES);
     n.customizeSummaryOptions({
         avg: true,
         count: false,
@@ -75,7 +73,8 @@ tr.exportTo('tr.metrics.v8', function() {
   }
 
   function createNumericForIdleTime() {
-    var n = numericBuilder.build();
+    var n = new tr.v.Histogram(
+        timeDurationInMs_smallerIsBetter, CUSTOM_BOUNDARIES);
     n.customizeSummaryOptions({
         avg: true,
         count: false,
@@ -89,7 +88,7 @@ tr.exportTo('tr.metrics.v8', function() {
   }
 
   function createPercentage(numerator, denominator) {
-    var hist = PERCENTAGE_BUILDER.build();
+    var hist = new tr.v.Histogram(percentage_biggerIsBetter);
     if (denominator === 0)
       hist.add(0);
     else
@@ -261,13 +260,13 @@ tr.exportTo('tr.metrics.v8', function() {
           var mutatorUtilization = tr.metrics.v8.utils.mutatorUtilization(
               0, time, WINDOW_SIZE_MS, pauses);
           [0.90, 0.95, 0.99].forEach(function(percent) {
-            var hist = PERCENTAGE_BUILDER.build();
+            var hist = new tr.v.Histogram(percentage_biggerIsBetter);
             hist.add(mutatorUtilization.percentile(1.0 - percent));
             values.addValue(new tr.v.NumericValue(
                 'v8-execute-mutator-utilization_pct_0' + percent * 100,
                 hist));
           });
-          var hist = PERCENTAGE_BUILDER.build();
+          var hist = new tr.v.Histogram(percentage_biggerIsBetter);
           hist.add(mutatorUtilization.min);
           values.addValue(new tr.v.NumericValue(
               'v8-execute-mutator-utilization_min', hist));