Add constructors for JSArray

sdk/lib/_internal/lib/js_primitives.dart

Index: sdk/lib/_internal/lib/js_primitives.dart
diff --git a/sdk/lib/_internal/lib/js_primitives.dart b/sdk/lib/_internal/lib/js_primitives.dart
index 86a405eb2918b94f6ebfc910db87bf4e9d2dd0b3..3315040636019394590ae862bc595a16975ce4a6 100644
--- a/sdk/lib/_internal/lib/js_primitives.dart
+++ b/sdk/lib/_internal/lib/js_primitives.dart
@@ -9,10 +9,6 @@ library dart2js._js_primitives;
 import 'dart:_foreign_helper' show
     JS;
 
-import 'dart:_interceptors' show
-    JSExtendableArray,
-    JSFixedArray;
-
 /**
  * This is the low-level method that is used to implement [print].  It is
  * possible to override this function from JavaScript by defining a function in
@@ -52,16 +48,3 @@ void printString(String string) {
   // avoid using Dart [:throw:] and Dart [toString].
   JS('void', 'throw "Unable to print message: " + String(#)', string);
 }
-
-List newGrowableList(length) {
-  return JS('JSExtendableArray', r'new Array(#)', length);
-}
-
-List newFixedList(length) {
-  return markFixedList(JS('', r'new Array(#)', length));
-}
-
-List markFixedList(List list) {
-  JS('void', r'#.fixed$length = #', list, true);
-  return JS('JSFixedArray', '#', list);
-}