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

components/startup_metric_utils/browser/startup_metric_utils.cc

Index: components/startup_metric_utils/browser/startup_metric_utils.cc
diff --git a/components/startup_metric_utils/browser/startup_metric_utils.cc b/components/startup_metric_utils/browser/startup_metric_utils.cc
index 03760ca0733a8c06b5920ee6f59f31b678e8f8b1..9fd7d911ae0d256bcb9acba29c430e88f0c6e820 100644
--- a/components/startup_metric_utils/browser/startup_metric_utils.cc
+++ b/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();