Add List.insert.

runtime/lib/byte_array.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 patch class Int8List {
   /* patch */ factory Int8List(int length) {
     return new _Int8Array(length);
   }
 
   /* patch */ factory Int8List.transferable(int length) {
@@ skipping 1973 matching lines @@
   void clear() {
     throw new UnsupportedError(
         "Cannot remove from a non-extendable array");
   }
 
   int removeLast() {
     throw new UnsupportedError(
         "Cannot remove from a non-extendable array");
   }
 
+  void insertAt(int index, int element) {
+    throw new UnsupportedError(
+        "Cannot add to a non-extendable array");
+  }
+
   int removeAt(int index) {
     throw new UnsupportedError(
         "Cannot remove from a non-extendable array");
   }
 
   void remove(Object element) {
     throw new UnsupportedError(
         "Cannot remove from a non-extendable array");
   }
 
@@ skipping 680 matching lines @@
   ByteArray asByteArray([int start = 0, int length]) {
     if (length == null) {
       length = this.lengthInBytes();
     }
     _rangeCheck(this.length, start, length);
     return _array.subByteArray(_offset + start, length);
   }
 
   static const int _BYTES_PER_ELEMENT = 8;
 }