Add some more categories for V8.TodoMVC to see what keeps us non-idle

BUG=636405
R=skyostil@chromium.org
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.perf:android_s5_perf_cq;master.tryserver.chromium.perf:linux_perf_cq;master.tryserver.chromium.perf:mac_retina_perf_cq;master.tryserver.chromium.perf:winx64_10_perf_cq

Review-Url: https://codereview.chromium.org/2274933002
Cr-Commit-Position: refs/heads/master@{#414187}

tools/perf/benchmarks/v8.py

@@ -23,6 +23,7 @@ from telemetry.web_perf import timeline_based_measurement
 def CreateV8TimelineBasedMeasurementOptions():
   category_filter = chrome_trace_category_filter.ChromeTraceCategoryFilter()
   category_filter.AddIncludedCategory('v8')
+  category_filter.AddIncludedCategory('blink')
   category_filter.AddIncludedCategory('blink.console')
   category_filter.AddDisabledByDefault('disabled-by-default-v8.compile')
   options = timeline_based_measurement.Options(category_filter)

tools/perf/page_sets/todomvc.py

@@ -39,10 +39,13 @@ class TodoMVCPage(page_module.Page):
         """
         this.becameIdle = false;
         this.idleCallback = function(deadline) {
-            if (deadline.timeRemaining() > 20)
+            let idletime = deadline.timeRemaining();
+            console.time("time remaining: " + idletime);
+            if (idletime > 20)
                 this.becameIdle = true;
             else
                 requestIdleCallback(this.idleCallback);
+            console.timeEnd("time remaining: " + idletime);
         };
         requestIdleCallback(this.idleCallback);
         """