[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 dd776dbc8c354722c692c3580914398e5de26d30..33684163f86a55c0e65ed9e612d0607ebbcb14ca 100644
--- a/src/runtime.js
+++ b/src/runtime.js
@@ -63,6 +63,8 @@ var TO_NUMBER;
 var TO_STRING;
 var TO_NAME;
 
+var $createEmptyArray;
+var $createStrongEmptyArray;
 var $defaultNumber;
 var $defaultString;
 var $NaN;
@@ -984,6 +986,15 @@ function ToPositiveInteger(x, rangeErrorIndex) {
   return i;
 }
 
+function CreateEmptyArray() {
+  return [];
+}
+
+function CreateStrongEmptyArray() {
+  "use strong";
+  return [];
+}
+
 //----------------------------------------------------------------------------
 
 // NOTE: Setting the prototype for Array must take place as early as
@@ -1014,5 +1025,7 @@ $toPositiveInteger = ToPositiveInteger;
 $toPrimitive = ToPrimitive;
 $toString = ToString;
 $toUint32 = ToUint32;
+$createEmptyArray = CreateEmptyArray
+$createStrongEmptyArray = CreateStrongEmptyArray;
 
 })