[promises] Remove one runtime call to create_resolving_functions

src/promise-utils.h

+// 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.
+
+#ifndef V8_PROMISE_UTILS_H_
+#define V8_PROMISE_UTILS_H_
+
+#include "src/objects.h"
+
+namespace v8 {
+namespace internal {
+
+class PromiseUtils : public AllStatic {

[adamk, 2016/11/10 18:10:54]

Please add a comment for this class.

[gsathya, 2016/11/11 02:34:37]

Done. Feel free to suggest something better.

+ public:
+  enum PromiseResolvingFunctionContextSlot {

[adamk, 2016/11/10 18:10:54]

Looks like this is no longer used?

[gsathya, 2016/11/11 02:34:37]

Done.

+    kAlreadyVisitedSlot = 4,
+    kPromiseSlot,
+    kDebugEventSlot,
+  };
+
+  static MUST_USE_RESULT Handle<JSObject> GetPromise(Isolate* isolate,
+                                                     Handle<Context> context);

[adamk, 2016/11/10 18:10:55]

Please add a comment for this block of functions; especially interesting is what
the Context argument is.

[gsathya, 2016/11/11 02:34:37]

Done.

+  static MUST_USE_RESULT Handle<Object> GetDebugEvent(Isolate* isolate,
+                                                      Handle<Context> context);
+  static MUST_USE_RESULT Handle<Smi> GetAlreadyVisited(Isolate* isolate,

[adamk, 2016/11/10 18:10:54]

MUST_USE_RESULT on a Handle generally isn't necessary; the way we try to use it
is to signal that an exception could be thrown (and it's usually used in concert
with a MaybeHandle).

[gsathya, 2016/11/11 02:34:37]

Done.

+                                                       Handle<Context> context);
+  static void SetAlreadyVisitedToTrue(Handle<Context> context);

[adamk, 2016/11/10 18:10:55]

SetAlreadyVisited() is a good enough name, I'd say.

[gsathya, 2016/11/11 02:34:37]

Done.

+
+  static void CreateResolvingFunctions(Isolate* isolate,
+                                       Handle<JSObject> promise,
+                                       Handle<Object> debug_event,
+                                       Handle<JSFunction>* resolve,
+                                       Handle<JSFunction>* reject);
+};
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_PROMISE_UTILS_H_