Revert of Create JSPromise

src/isolate.cc

Index: src/isolate.cc
diff --git a/src/isolate.cc b/src/isolate.cc
index d3ab6aa75f876e1c5110b9f32cfae672ea128331..42a5a55b9d622a39ecf8cea37bcf555a7329b47f 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -3160,15 +3160,23 @@
   Handle<Object> tasks(info->tasks(), this);
   Handle<JSFunction> promise_handle_fn = promise_handle();
   Handle<Object> undefined = factory()->undefined_value();
-  Handle<Object> deferred(info->deferred(), this);
-
-  if (deferred->IsFixedArray()) {
-    DCHECK(tasks->IsFixedArray());
-    Handle<FixedArray> deferred_arr = Handle<FixedArray>::cast(deferred);
-    Handle<FixedArray> tasks_arr = Handle<FixedArray>::cast(tasks);
-    for (int i = 0; i < deferred_arr->length(); i++) {
-      Handle<Object> argv[] = {value, handle(tasks_arr->get(i), this),
-                               handle(deferred_arr->get(i), this)};
+
+  // If tasks is an array we have multiple onFulfilled/onRejected callbacks
+  // associated with the promise. The deferred object for each callback
+  // is attached to this array as well.
+  // Otherwise, there is a single callback and the deferred object is attached
+  // directly to PromiseReactionJobInfo.
+  if (tasks->IsJSArray()) {
+    Handle<JSArray> array = Handle<JSArray>::cast(tasks);
+    DCHECK(array->length()->IsSmi());
+    int length = Smi::cast(array->length())->value();
+    ElementsAccessor* accessor = array->GetElementsAccessor();
+    DCHECK(length % 2 == 0);
+    for (int i = 0; i < length; i += 2) {
+      DCHECK(accessor->HasElement(array, i));
+      DCHECK(accessor->HasElement(array, i + 1));
+      Handle<Object> argv[] = {value, accessor->Get(array, i),
+                               accessor->Get(array, i + 1)};
       *result = Execution::TryCall(this, promise_handle_fn, undefined,
                                    arraysize(argv), argv, maybe_exception);
       // If execution is terminating, just bail out.
@@ -3177,6 +3185,7 @@
       }
     }
   } else {
+    Handle<Object> deferred(info->deferred(), this);
     Handle<Object> argv[] = {value, tasks, deferred};
     *result = Execution::TryCall(this, promise_handle_fn, undefined,
                                  arraysize(argv), argv, maybe_exception);