Remove =List in JS, use JSExtendableArray instead.

sdk/lib/_internal/lib/foreign_helper.dart

Index: sdk/lib/_internal/lib/foreign_helper.dart
===================================================================
--- sdk/lib/_internal/lib/foreign_helper.dart	(revision 24309)
+++ sdk/lib/_internal/lib/foreign_helper.dart	(working copy)
@@ -34,10 +34,6 @@
  * [typeDescription] has several extensions to help describe the behavior more
  * accurately.  In addition to the union type already described:
  *
- *  + `=List` is the JavaScript array type.  This is more precise than `List`,
- *     which includes about fifty DOM types that also implement the List
- *     interface.
- *
  *  + `=Object` is a plain JavaScript object.  Some DOM methods return instances
  *     that have no corresponing Dart type (e.g. cross-frame documents),
  *     `=Object` can be used to describe these untyped' values.
@@ -47,9 +43,6 @@
  *
  * Examples:
  *
- *     // Create a JavaScript Array.
- *     List a = JS('=List', 'new Array(#)', length);
- *
  *     // Parent window might be an opaque cross-frame window.
  *     var thing = JS('=Object|Window', '#.parent', myWindow);
  *