[inspector] async stacks for Promise.then calls...

src/js/promise.js

Index: src/js/promise.js
diff --git a/src/js/promise.js b/src/js/promise.js
index d66ae1a9ca40b293886ba6745ab866e7b94f3042..ec50f11d22d20ed165848df24eaedc12d743d6a6 100644
--- a/src/js/promise.js
+++ b/src/js/promise.js
@@ -39,9 +39,8 @@ utils.Import(function(from) {
 
 // Core functionality.
 
-function PromiseDebugGetInfo(deferreds, status) {
-  var id, name, instrumenting = DEBUG_IS_ACTIVE;
-
+function PromiseDebugGetInfo(deferreds, status, id) {
+  var name, instrumenting = DEBUG_IS_ACTIVE;
   if (instrumenting) {
     // In an async function, reuse the existing stack related to the outer
     // Promise. Otherwise, e.g. in a direct call to then, save a new stack.
@@ -57,9 +56,7 @@ function PromiseDebugGetInfo(deferreds, status) {
                        promiseAsyncStackIDSymbol);
       name = "async function";
     } else {
-      id = %DebugNextMicrotaskId();
       name = status === kFulfilled ? "Promise.resolve" : "Promise.reject";
-      %DebugAsyncTaskEvent("enqueue", id, name);
     }
   }
   return [id, name];