[bisect] - Have compare_samples check for missing "summary" tracename.

tracing/tracing/metrics/compare_samples_cmdline.html

Index: tracing/tracing/metrics/compare_samples_cmdline.html
diff --git a/tracing/tracing/metrics/compare_samples_cmdline.html b/tracing/tracing/metrics/compare_samples_cmdline.html
index 3d9ce69d021868c339ae721047490ab1a077185d..ca5454e89775fe9a356d71a76df8dee38dea1ab7 100644
--- a/tracing/tracing/metrics/compare_samples_cmdline.html
+++ b/tracing/tracing/metrics/compare_samples_cmdline.html
@@ -47,6 +47,14 @@ function geoMeanFromHistogram(h) {
   return Math.exp(sumOfLogs / count);
 }
 
+function guessFullTIRMetricName(metricName) {
+  var parts = metricName.split('/');
+  if (parts.length === 2) {
+    return metricName + '/summary';
+  }
+  return undefined;
+}
+
 function splitMetric(metricName) {
   var parts = metricName.split('/');
   var interactionName;
@@ -85,6 +93,19 @@ function valuesFromCharts(listOfCharts, metricName) {
   return allValues;
 }
 
+function valuesFromChartsWithFallback(listOfCharts, metricName) {
+  var allValues = valuesFromCharts(listOfCharts, metricName);
+  if (allValues.length > 0)
+    return allValues;
+
+  // If this had a tir_label, the "summary" part may have been stripped by
+  // the dashboard during upload. We can re-add it here.
+  var fullMetricName = guessFullTIRMetricName(metricName);
+  if (!fullMetricName)
+    return [];
+  return valuesFromCharts(listOfCharts, fullMetricName);
+}
+
 function rawValuesByMetricName(valueSet, metricName) {
   var interactionRecord;
   var valueName;
@@ -249,8 +270,8 @@ var SampleComparison = {
     var bPaths = chartPathListB.split(',');
     var chartsA = parseFiles(aPaths);
     var chartsB = parseFiles(bPaths);
-    var sampleA = valuesFromCharts(chartsA, metric);
-    var sampleB = valuesFromCharts(chartsB, metric);
+    var sampleA = valuesFromChartsWithFallback(chartsA, metric);
+    var sampleB = valuesFromChartsWithFallback(chartsB, metric);
     return buildComparisonResultOutput(sampleA, sampleB);
   }