[promisehook] Implement PromiseHook

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index dfa0f06cb8ebc2099495bad9bcf6d0210b2a7597..04e7c894d4584e3d4cce1ad50b73b22885acfff4 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -8260,6 +8260,10 @@ void Isolate::RemoveCallCompletedCallback(
       reinterpret_cast<CallCompletedCallback>(callback));
 }
 
+void Isolate::SetPromiseHook(PromiseHook hook) {
+  i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
+  isolate->SetPromiseHook(hook);
+}
 
 void Isolate::SetPromiseRejectCallback(PromiseRejectCallback callback) {
   if (callback == NULL) return;