Add support for allowing an embedder to get the V8 profile timer event logs.

src/v8.cc

Index: src/v8.cc
diff --git a/src/v8.cc b/src/v8.cc
index a415f26197b7f5cf9d001823c39021bef4d7703c..8e19638a1b1e1ced2e09d3e5f636dc2db0cb1c6e 100644
--- a/src/v8.cc
+++ b/src/v8.cc
@@ -51,6 +51,13 @@
 namespace v8 {
 namespace internal {
 
+static void empty_log_internal_events(const char* name, int se) { return; }

[Yang, 2014/03/06 12:05:33]

I think we can remove that return statement too. just an empty { } should be
fine.

[fmeawad, 2014/03/06 19:23:04]

Done.

+
+static void log_internal_events(const char* name, int se) {
+  Isolate* isolate = Isolate::Current();
+  LOG(isolate, Logger::TimerEvent(static_cast<Logger::StartEnd>(se), name));
+}
+
 V8_DECLARE_ONCE(init_once);
 
 List<CallCompletedCallback>* V8::call_completed_callbacks_ = NULL;
@@ -79,6 +86,12 @@ bool V8::Initialize(Deserializer* des) {
   if (isolate->IsDead()) return false;
   if (isolate->IsInitialized()) return true;
 
+  if (!isolate->event_logger() && FLAG_log_internal_timer_events) {
+    isolate->set_event_logger(log_internal_events);
+  } else {
+    isolate->set_event_logger(empty_log_internal_events);
+  }

[Yang, 2014/03/06 12:05:33]

I think this should be put into Isolate::Init. And I think the callbacks should
be moved to log.h.

[fmeawad, 2014/03/06 19:23:04]

Done.

+
 #ifdef V8_USE_DEFAULT_PLATFORM
   DefaultPlatform* platform = static_cast<DefaultPlatform*>(platform_);
   platform->SetThreadPoolSize(isolate->max_available_threads());