Support tracing metrics for measureTime & measureFrameTime method in blink_perf

tools/perf/benchmarks/blink_perf.js

Index: tools/perf/benchmarks/blink_perf.js
diff --git a/tools/perf/benchmarks/blink_perf.js b/tools/perf/benchmarks/blink_perf.js
index 465e1ffd7409837bc95bf5c05a6b1e3f49718e84..bb764cf4f7715547391d08fb3c30594e1db5d755 100644
--- a/tools/perf/benchmarks/blink_perf.js
+++ b/tools/perf/benchmarks/blink_perf.js
@@ -12,6 +12,24 @@ testRunner.notifyDone = function() {
   this.isDone = true;
 };
 
+testRunner.supportTracing = true;
+
+// If this is true, blink_perf tests is put on paused waiting for tracing to
+// be started. |scheduleTestRun| should be invoked after tracing is started
+// to continue blink perf test.
+testRunner.isWaitingForTracingStart = false;
+
+testRunner.startTracing = function(tracingCategories, scheduleTestRun) {
+  this.tracingCategories = tracingCategories;
+  this.scheduleTestRun = scheduleTestRun;
+  this.isWaitingForTracingStart = true;
+}
+
+testRunner.stopTracingAndMeasure = function(traceEventsToMeasure, callback) {
+  testRunner.traceEventsToMeasure = traceEventsToMeasure;
+  callback();
+}
+
 window.GCController = {};
 
 GCController.collect = function() {