[promises] Port ResolvePromise to TF

src/promise-utils.h

Index: src/promise-utils.h
diff --git a/src/promise-utils.h b/src/promise-utils.h
index 6ed6fcde5f2188c4668fc7330cb70613d5719c3b..2748853f86a09d8957af3c851ba575b2799c0346 100644
--- a/src/promise-utils.h
+++ b/src/promise-utils.h
@@ -5,6 +5,7 @@
 #ifndef V8_PROMISE_UTILS_H_
 #define V8_PROMISE_UTILS_H_
 
+#include "src/contexts.h"
 #include "src/objects.h"
 
 namespace v8 {
@@ -13,6 +14,13 @@ namespace internal {
 // Helper methods for Promise builtins.
 class PromiseUtils : public AllStatic {
  public:
+  enum PromiseResolvingFunctionContextSlot {

[jgruber, 2016/12/07 12:59:38]

Please document these (if not already done elsewhere).

Thinking about this some more, are there any situations where we will conflict
with other code by blindly storing into specific context slots? 

[gsathya, 2016/12/08 05:18:15]

Done.
These are unused slots, so it's fine

+    kAlreadyVisitedSlot = Context::MIN_CONTEXT_SLOTS,
+    kPromiseSlot,
+    kDebugEventSlot,
+    kPromiseContextLength,
+  };
+
   // These get and set the slots on the PromiseResolvingContext, which
   // is used by the resolve/reject promise callbacks.
   static JSObject* GetPromise(Handle<Context> context);