[promises] Move CreateResolvingFunctions to c++

src/factory.cc

Index: src/factory.cc
diff --git a/src/factory.cc b/src/factory.cc
index 564f821c42875dd1e14e68d0344678b1fe9f8dc0..6ed090e265397a062395f1cc35bcc73557f6e913 100644
--- a/src/factory.cc
+++ b/src/factory.cc
@@ -962,6 +962,21 @@ Handle<Context> Factory::NewBlockContext(Handle<JSFunction> function,
   return context;
 }
 
+Handle<Context> Factory::NewPromiseResolvingFunctionContext(
+    Handle<JSFunction> function, Handle<Cell> already_visited,
+    Handle<JSObject> promise, Handle<Object> debug_event) {
+  Handle<FixedArray> array = NewFixedArray(Context::MIN_CONTEXT_SLOTS + 3);
+  array->set_map_no_write_barrier(*function_context_map());
+  Handle<Context> context = Handle<Context>::cast(array);
+  context->set_closure(*function);
+  context->set_previous(function->context());
+  context->set_extension(*the_hole_value());
+  context->set_native_context(function->native_context());
+  context->set(4, *already_visited);
+  context->set(5, *promise);
+  context->set(6, *debug_event);

[adamk, 2016/11/08 18:09:55]

Looks like if you let the caller do the setting, you could have those enums
defined only in builtins-promise.cc (and pass in the length too).

[gsathya, 2016/11/08 20:03:19]

NewDebugEvaluateContext and NewCatchContext have a magic length, so I'm leaving
the length here as such. But, I guess they set all the values in the function
itself, so it's easier to figure out what the magic number means.  Let me know
if you'd rather have me pass it in as an argument.

+  return context;
+}
 
 Handle<Struct> Factory::NewStruct(InstanceType type) {
   CALL_HEAP_FUNCTION(