[promises] cleanup default promise handlers

src/js/promise.js

Index: src/js/promise.js
diff --git a/src/js/promise.js b/src/js/promise.js
index 95ab793591c04e3f2c3932a89b85f2742842cadf..27571daabbefe3d142701587b13f4ed6f6c1f36f 100644
--- a/src/js/promise.js
+++ b/src/js/promise.js
@@ -19,14 +19,6 @@ var promiseForwardingHandlerSymbol =
 var GlobalPromise = global.Promise;
 
 // -------------------------------------------------------------------
-
-// Core functionality.
-
-function PromiseIdResolveHandler(x) { return x; }
-function PromiseIdRejectHandler(r) { %_ReThrow(r); }
-SET_PRIVATE(PromiseIdRejectHandler, promiseForwardingHandlerSymbol, true);
-
-// -------------------------------------------------------------------
 // Define exported functions.
 
 // Combinators.
@@ -137,9 +129,4 @@ utils.InstallFunctions(GlobalPromise, DONT_ENUM, [
   "race", PromiseRace,
 ]);
 
-%InstallToContext([
-  "promise_id_resolve_handler", PromiseIdResolveHandler,
-  "promise_id_reject_handler", PromiseIdRejectHandler
-]);
-
 })