Fix treatment of rest pattern in array destructuring.

src/js/runtime.js

Index: src/js/runtime.js
diff --git a/src/js/runtime.js b/src/js/runtime.js
index 7a61094da62d4bcd07b10d4a0ebb12fa7a0d809f..8e4f2832568138ccb77e903c5f02669413364d34 100644
--- a/src/js/runtime.js
+++ b/src/js/runtime.js
@@ -42,14 +42,6 @@ utils.ImportFromExperimental(function(from) {
    ---------------------------------
 */
 
-function ConcatIterableToArray(target, iterable) {
-   var index = target.length;
-   for (var element of iterable) {
-     AddIndexedProperty(target, index++, element);
-   }
-   return target;
-}
-
 
 // This function should be called rather than %AddElement in contexts where the
 // argument might not be less than 2**32-1. ES2015 ToLength semantics mean that
@@ -137,8 +129,4 @@ utils.Export(function(to) {
   to.SpeciesConstructor = SpeciesConstructor;
 });
 
-%InstallToContext([
-  "concat_iterable_to_array", ConcatIterableToArray,
-]);
-
 })