[es6] re-implement rest parameters via desugaring

src/runtime.js

Index: src/runtime.js
diff --git a/src/runtime.js b/src/runtime.js
index e5ac2210528c7ef46d58f05de1cb0b41468498c2..e04f347b1d9dd372b53ed0d5f3448d76b2b7d9f3 100644
--- a/src/runtime.js
+++ b/src/runtime.js
@@ -63,6 +63,7 @@ var TO_NUMBER;
 var TO_STRING;
 var TO_NAME;
 
+var $createEmptyArray;
 var $defaultNumber;
 var $defaultString;
 var $NaN;
@@ -966,6 +967,10 @@ function ToPositiveInteger(x, rangeErrorIndex) {
   return i;
 }
 
+function CreateEmptyArray() {
+  return [];
+}
+
 //----------------------------------------------------------------------------
 
 // NOTE: Setting the prototype for Array must take place as early as
@@ -996,5 +1001,5 @@ $toPositiveInteger = ToPositiveInteger;
 $toPrimitive = ToPrimitive;
 $toString = ToString;
 $toUint32 = ToUint32;
-
+$createEmptyArray = CreateEmptyArray;
 })