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

src/log.h

Index: src/log.h
diff --git a/src/log.h b/src/log.h
index d4dc76a21cc5222139e209646505caf90534d16a..09b6b77740b5d716b66fc2af1869d49a3299f072 100644
--- a/src/log.h
+++ b/src/log.h
@@ -316,15 +316,18 @@ class Logger {
   static void EnterExternal(Isolate* isolate);
   static void LeaveExternal(Isolate* isolate);
 
+  static void EmptyLogInternalEvents(const char* name, int se) { }
+  static void LogInternalEvents(const char* name, int se);
+
   class TimerEventScope {
    public:
     TimerEventScope(Isolate* isolate, const char* name)
         : isolate_(isolate), name_(name) {
-      if (FLAG_log_internal_timer_events) LogTimerEvent(START);
+      LogTimerEvent(START);
     }
 
     ~TimerEventScope() {
-      if (FLAG_log_internal_timer_events) LogTimerEvent(END);
+      LogTimerEvent(END);
     }
 
     void LogTimerEvent(StartEnd se);