Implement a new flow event API that allows binding flow events and regular events.

ui/gl/angle_platform_impl.cc

Index: ui/gl/angle_platform_impl.cc
diff --git a/ui/gl/angle_platform_impl.cc b/ui/gl/angle_platform_impl.cc
index a405f8e0859e1d577b9b18108b8aae5ea1523ac5..3e6e590f989d203b10abddbb5892ab047b1d3ac0 100644
--- a/ui/gl/angle_platform_impl.cc
+++ b/ui/gl/angle_platform_impl.cc
@@ -44,9 +44,18 @@ angle::Platform::TraceEventHandle ANGLEPlatformImpl::addTraceEvent(
       base::TraceTicks() + base::TimeDelta::FromSecondsD(timestamp);
   base::trace_event::TraceEventHandle handle =
       TRACE_EVENT_API_ADD_TRACE_EVENT_WITH_THREAD_ID_AND_TIMESTAMP(
-          phase, category_group_enabled, name, id, trace_event_internal::kNoId,
-          base::PlatformThread::CurrentId(), timestamp_tt, num_args, arg_names,
-          arg_types, arg_values, nullptr, flags);
+          phase,
+          category_group_enabled,
+          name,
+          id,

[dsinclair, 2015/07/21 18:11:49]

This shouldn't need to change because we added the overloads, right?

[yuhaoz, 2015/07/21 18:22:34]

Same as the ppapi case. I removed the kNoId that fmeawad@ added for context_id.

+          base::PlatformThread::CurrentId(),
+          timestamp_tt,
+          num_args,
+          arg_names,
+          arg_types,
+          arg_values,
+          NULL,

[vmpstr, 2015/07/21 18:03:41]

nit: keep nullptr, please.

+          flags);
   angle::Platform::TraceEventHandle result;
   memcpy(&result, &handle, sizeof(result));
   return result;