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

content/child/blink_platform_impl.cc

Index: content/child/blink_platform_impl.cc
diff --git a/content/child/blink_platform_impl.cc b/content/child/blink_platform_impl.cc
index 500ba382d379bb95371ce42a0dcd95ea1e6cc72e..a99c8b120622841b1d01b09280df276609b97119 100644
--- a/content/child/blink_platform_impl.cc
+++ b/content/child/blink_platform_impl.cc
@@ -638,9 +638,18 @@ blink::Platform::TraceEventHandle BlinkPlatformImpl::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, NULL, flags);
+          phase,
+          category_group_enabled,
+          name,
+          id,
+          base::PlatformThread::CurrentId(),
+          timestamp_tt,
+          num_args,

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

Why unwrapped?

+          arg_names,
+          arg_types,
+          arg_values,
+          NULL,
+          flags);
   blink::Platform::TraceEventHandle result;
   memcpy(&result, &handle, sizeof(result));
   return result;
@@ -674,9 +683,18 @@ blink::Platform::TraceEventHandle BlinkPlatformImpl::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, convertable_wrappers, flags);
+          phase,
+          category_group_enabled,
+          name,
+          id,
+          base::PlatformThread::CurrentId(),
+          timestamp_tt,
+          num_args,
+          arg_names,

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

ditto

+          arg_types,
+          arg_values,
+          convertable_wrappers,
+          flags);
   blink::Platform::TraceEventHandle result;
   memcpy(&result, &handle, sizeof(result));
   return result;