Replace AddProperty by AddNamedProperty to speed up the common case

src/promise.js

Index: src/promise.js
diff --git a/src/promise.js b/src/promise.js
index c94e05968dac17b9bb7a5bbee3bacf2aa42c85da..2797d79acbc83941058bc7f189dc228957fc82c9 100644
--- a/src/promise.js
+++ b/src/promise.js
@@ -325,7 +325,7 @@ var lastMicrotaskId = 0;
   // Install exported functions.
 
   %CheckIsBootstrapping();
-  %AddProperty(global, 'Promise', $Promise, DONT_ENUM);
+  %AddNamedProperty(global, 'Promise', $Promise, DONT_ENUM);
   InstallFunctions($Promise, DONT_ENUM, [
     "defer", PromiseDeferred,
     "accept", PromiseResolved,