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

base/trace_event/common/trace_event_common.h

Index: base/trace_event/common/trace_event_common.h
diff --git a/base/trace_event/common/trace_event_common.h b/base/trace_event/common/trace_event_common.h
index 33578bd37bd2583fb7c99cce4bb7ab14614906a2..1cca01dc9c5a108fd7596d2c5abab2189d23ef98 100644
--- a/base/trace_event/common/trace_event_common.h
+++ b/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_TIMESTAMP(category_group, name, scope, \

[shatch, 2015/11/13 17:32:04]

Should this be TRACE_EVENT_MARK_WITH_TIMESTAMP0 and grouped with the _TIMESTAMP1
below?

[gabadie, 2015/11/16 12:09:03]

Actually not really. I asked charliea@chromium.org (who is in charge of
implementing the mark & measure standardized JS API) about this, and there is a
difference between an INSTANT event and a MARK event. A mark EVENT is pretty
much an INSTANT event. However the MARK event get also referenced on C++ side so
the JS API mark & measure can access it. If I was using MARK events, then these
startup specific events would be accessible on the w3c standardized API
(http://www.w3.org/TR/user-timing/), and we don't what that.

[shatch, 2015/11/16 14:58:30]

So should you be using TRACE_EVENT_PHASE_INSTANT instead, since you don't want
to use a MARK event but your macro specifies TRACE_EVENT_PHASE_MARK?

[gabadie, 2015/11/16 15:36:18]

Oups... Turned out one commit was missing in my branch. Good catch! My bad.

Fixed. =)

+                                           timestamp)                   \
+  INTERNAL_TRACE_EVENT_ADD_WITH_ID_TID_AND_TIMESTAMP(                   \
+      TRACE_EVENT_PHASE_MARK, category_group, name, 0, 0, timestamp,    \
+      TRACE_EVENT_FLAG_NONE)
+
 // 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)