Implements AddStartupEventsForTelemetry() in startup_metric_utils.cc for...

Implements AddStartupEventsForTelemetry() in startup_metric_utils.cc for in-coming startup telemetry benchmarks using TBM.

BUG=539287
CQ_EXTRA_TRYBOTS=tryserver.chromium.perf:linux_perf_bisect;tryserver.chromium.perf:mac_10_10_perf_bisect;tryserver.chromium.perf:win_perf_bisect;tryserver.chromium.perf:android_nexus5_perf_bisect

Review URL: https://codereview.chromium.org/1410943005

Cr-Commit-Position: refs/heads/master@{#360592}

base/trace_event/common/trace_event_common.h

@@ -309,6 +309,12 @@
                            TRACE_EVENT_FLAG_COPY | scope, arg1_name, arg1_val, \
                            arg2_name, arg2_val)
 
+#define TRACE_EVENT_INSTANT_WITH_TIMESTAMP0(category_group, name, scope, \
+                                           timestamp)                   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                   \
+      TRACE_EVENT_PHASE_INSTANT, category_group, name, 0, 0, timestamp, \
+      TRACE_EVENT_FLAG_NONE | scope)
+
 // Syntactic sugars for the sampling tracing in the main thread.
 #define TRACE_EVENT_SCOPED_SAMPLING_STATE(category, name) \
   TRACE_EVENT_SCOPED_SAMPLING_STATE_FOR_BUCKET(0, category, name)

components/startup_metric_utils/browser/startup_metric_utils.cc

@@ -319,6 +319,8 @@ void RecordMainEntryTimeHistogram() {
           (browser_main_entry_time_raw_ms >> 1) & kLower31BitsMask);
 
   // A timestamp is a 64 bit value, yet histograms can only store 32 bits.
+  // TODO(gabadie): Once startup_with_url.* benchmarks are replaced by
+  //    startup_with_url2.*, remove this dirty hack (crbug.com/539287).
   LOCAL_HISTOGRAM_TIMES("Startup.BrowserMainEntryTimeAbsoluteHighWord",
       browser_main_entry_time_raw_ms_high_word);
   LOCAL_HISTOGRAM_TIMES("Startup.BrowserMainEntryTimeAbsoluteLowWord",
@@ -357,6 +359,22 @@ base::TimeTicks ExeMainEntryPointTicks() {
   return base::TimeTicks();
 }
 
+void AddStartupEventsForTelemetry()
+{
+  DCHECK(!g_browser_main_entry_point_ticks.Get().is_null());
+
+  TRACE_EVENT_INSTANT_WITH_TIMESTAMP0(
+      "startup", "Startup.BrowserMainEntryPoint", 0,
+      g_browser_main_entry_point_ticks.Get().ToInternalValue());
+
+  if (!g_process_creation_ticks.Get().is_null())
+  {
+    TRACE_EVENT_INSTANT_WITH_TIMESTAMP0(
+        "startup", "Startup.BrowserProcessCreation", 0,
+        g_process_creation_ticks.Get().ToInternalValue());
+  }
+}
+
 }  // namespace
 
 bool WasNonBrowserUIDisplayed() {
@@ -394,6 +412,7 @@ void RecordExeMainEntryPointTime(const base::Time& time) {
 
 void RecordBrowserMainMessageLoopStart(const base::TimeTicks& ticks,
                                        bool is_first_run) {
+  AddStartupEventsForTelemetry();
   RecordHardFaultHistogram(is_first_run);
   RecordMainEntryTimeHistogram();