Add an API for additional profile log records

src/api.cc

Index: src/api.cc
===================================================================
--- src/api.cc	(revision 16936)
+++ src/api.cc	(working copy)
@@ -6314,6 +6314,12 @@
 }
 
 
+void V8::AddProfilerMark(char* mark) {
+  i::Isolate* isolate = i::Isolate::Current();
+  LOG(isolate, MarkEvent(mark));
+}
+
+
 HeapProfiler* Isolate::GetHeapProfiler() {
   i::HeapProfiler* heap_profiler =
       reinterpret_cast<i::Isolate*>(this)->heap_profiler();