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

src/js/async-await.js

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 (function(global, utils, extrasUtils) {
 
 "use strict";
 
 %CheckIsBootstrapping();
 
 // -------------------------------------------------------------------
 // Imports
 
 var AsyncFunctionNext;
 var AsyncFunctionThrow;
 
 utils.Import(function(from) {
   AsyncFunctionNext = from.AsyncFunctionNext;
   AsyncFunctionThrow = from.AsyncFunctionThrow;
 });
 
-var promiseAsyncStackIDSymbol =
-    utils.ImportNow("promise_async_stack_id_symbol");
 var promiseHandledBySymbol =
     utils.ImportNow("promise_handled_by_symbol");
 var promiseForwardingHandlerSymbol =
     utils.ImportNow("promise_forwarding_handler_symbol");
 
 // -------------------------------------------------------------------
 
 function PromiseCastResolved(value) {
   // TODO(caitp): This is non spec compliant. See v8:5694.
   if (%is_promise(value)) {
@@ skipping 78 matching lines @@
 function RejectPromiseNoDebugEvent(promise, reason) {
   return %PromiseReject(promise, reason, false);
 }
 
 function AsyncFunctionPromiseCreate() {
   var promise = %promise_internal_constructor(UNDEFINED);
   if (DEBUG_IS_ACTIVE) {
     // Push the Promise under construction in an async function on
     // the catch prediction stack to handle exceptions thrown before
     // the first await.
-    %DebugPushPromise(promise);
     // Assign ID and create a recurring task to save stack for future
     // resumptions from await.
-    var id = %DebugNextMicrotaskId();
-    SET_PRIVATE(promise, promiseAsyncStackIDSymbol, id);
-    %DebugAsyncTaskEvent(kEnqueueRecurring, id, kAsyncFunction);
+    %DebugAsyncFunctionPromiseCreated(promise);
   }
   return promise;
 }
 
 function AsyncFunctionPromiseRelease(promise) {
   if (DEBUG_IS_ACTIVE) {
-    // Cancel
-    var id = GET_PRIVATE(promise, promiseAsyncStackIDSymbol);
-
-    // Don't send invalid events when catch prediction is turned on in
-    // the middle of some async operation.
-    if (!IS_UNDEFINED(id)) {
-      %DebugAsyncTaskEvent(kCancel, id, kAsyncFunction);
-    }
     // Pop the Promise under construction in an async function on
     // from catch prediction stack.
     %DebugPopPromise();
   }
 }
 
 %InstallToContext([
   "async_function_await_caught", AsyncFunctionAwaitCaught,
   "async_function_await_uncaught", AsyncFunctionAwaitUncaught,
   "reject_promise_no_debug_event", RejectPromiseNoDebugEvent,
   "async_function_promise_create", AsyncFunctionPromiseCreate,
   "async_function_promise_release", AsyncFunctionPromiseRelease,
 ]);
 
 })